added migrated 2.x add-ons

Signed-off-by: Kai Kreuzer <kai@openhab.org>

bundles/org.openhab.transform.regex/README.md

@@ -0,0 +1,106 @@
+# RegEx Transformation Service
+
+Transforms a source string on basis of the regular expression (regex) search pattern to a defined result string.
+
+The simplest regex is in the form `<regex>` and transforms the input string on basis of the regex pattern to a result string.
+A full regex is in the form `s/<regex>/<substitution>/g` whereat the delimiter `s` and the regex flag `g` have a special meaning.
+
+The regular expression in the format `s/<regex>/result/g`, replaces all occurrences of `<regex>` in the source string with `result`.
+The regular expression in the format `s/<regex>/result/` (without `g`), replaces the first occurrence of `<regex>` in the source string with `result`.
+
+If the regular expression contains a [capture group](https://docs.oracle.com/javase/8/docs/api/java/util/regex/Pattern.html#cg) defined by `()`, it returns the captured string. 
+Multiple capture groups can be used to retrieve multiple strings and can be combined as a result string defined in the `substitution`.
+
+The transformation can be set to be restricted to only match if the input string begins with a character by prepending `^` to the beginning of a pattern or to only match if the input string ends with a specified character by appending `$` at the end.
+So the regex `^I.*b$` only matches when the input string starts with `I` and ends with `b`, like in `I'm Bob`. Both can be used alone or in combination.
+
+The special characters `\.[]{}()*+-?^$|` have to be escaped when they should be used as literal characters.
+
+## Examples
+
+### Basic Examples
+
+|         Input String        |    Regular Expression    |         Output String        | Explanation              |
+|---------------------------|------------------------|----------------------------|--------------------------|
+| `My network does not work.` | `s/work/cast/g` | `"My netcast does not cast."` | Replaces all matches of the string "work" with the string "cast". |
+| `My network does not work.` | `.*(\snot).*` | `" not"` | Returns only the first match and strips of the rest, "\s" defines a  whitespace. |
+| `temp=44.0'C` | `temp=(.*?)'C)`          | `44.0` | Matches whole string and returns the content of the captcha group `(.?)`. |
+| `48312` | `s/(.{2})(.{3})/$1.$2/g` | `48.312` | Captures 2 and 3 character, returns first capture group adds a dot and the second capture group. This divides by 1000. |
+
+### Example In Setup
+
+**Input String**
+
+```shell
+temp=44.0'C
+```
+
+the regex transformation can be used to extract the value to display it on the label.
+
+**.items**
+
+```csv
+String  Temperature_str "Temperature [REGEX(.*=(\\d*.\\d*).*):%s °C]" {...}
+Number  Temperature "Temperature [%.1f °C]"
+```
+
+The regex pattern is is defined as follows
+* `.*` match any character, zero and unlimited times
+* `=` match the equal sign literally, used to find the position
+*  `()` capture group match 
+    * `\d*` match a digit (equal to [0-9]), zero and unlimited times, the backslash has to be escaped see [string vs plain](#Differences-to-plain-Regex)
+    * `.` match the dot literally
+    * `\w*` match a word character (equal to [a-zA-Z_0-9]), zero and unlimited times, the backslash has to be escaped see [string vs plain](#Differences-to-plain-Regex)
+* `.*` match any character, zero and unlimited times
+
+The result will be `44.0` and displayed on the label as `Temperature 44.0°C`.
+A better solution would be to use the regex on the result from the binding either in a rule or when the binding allows it on the output channel. 
+Thus the value `44.0` would be saved as a number.
+
+**.rules**
+
+```php
+rule "Convert String to Item Number"
+  when
+    Item Temperature_str changed
+ then
+    // use the transformation service to retrieve the value
+    val newValue = transform("REGEX", ".*=(\\d*.\\d*).*", Temperature_str.state.toString)
+
+    // post the new value to the Number Item
+    Temperature.postUpdate( newValue )
+ end
+```
+
+Now the resulting Number can also be used in the label to [change the color](https://docs.openhab.org/configuration/sitemaps.html#label-and-value-colors) or in a rule as value for comparison.
+
+## Differences to plain Regex
+
+The regex is embedded in a string so when double quotes `"` are used in a regex they need to be escaped `\"` to keep the string intact.
+As the escape character of strings is the backslash this has to be escaped additionally.
+To use a dot as literal in the regex it has to be escape `\.`, but in a string it has to be escaped twice `"\\."`.
+The first backslash escapes the second backslash in the string so it can be used in the regex.
+Using a backslash in a Regex as literal `\\` will have this form `"\\\\"`.
+
+## Usage as a Profile
+
+The functionality of this `TransformationService` can be used in a `Profile` on an `ItemChannelLink` too.
+To do so, it can be configured in the `.items` file as follows:
+
+```java
+String <itemName> { channel="<channelUID>"[profile="transform:REGEX", function="<regex>", sourceFormat="<valueFormat>"]}
+```
+
+The regular expression to be executed has to be set in the `function` parameter.
+The parameter `sourceFormat` is optional and can be used to format the input value **before** the transformation, i.e. `%.3f`.
+If omitted the default is `%s`, so the input value will be put into the transformation without any format changes.
+
+Please note: This profile is a one-way transformation, i.e. only values from a device towards the item are changed, the other direction is left untouched.
+
+## Further Reading
+
+* A full [introduction](https://www.w3schools.com/jsref/jsref_obj_regexp.asp) for regular expression is available at W3School.
+* Online validator help to check the syntax of a regex and give information how to design it.
+    * [Regex 101](https://regex101.com/)
+    * [Regex R](https://regexr.com/)
+    * [ExtendsClass](https://extendsclass.com/regex-tester.html)