commons-lang really is only used by some core classes to join strings or modiy arrays.
It's not worth carrying the dependency. This commit removes the dependency on commons-lang
entirely.
Follow up for https://github.com/elastic/elasticsearch-analysis-kuromoji/issues/61
We don't shade anymore elasticsearch dependencies, so plugins might include jars in the distribution ZIP file which might not be needed anymore.
For example, `elasticsearch-cloud-aws` comes with:
```
Archive: cloud-aws/target/releases/elasticsearch-cloud-aws-2.0.0-SNAPSHOT.zip
Length Date Time Name
-------- ---- ---- ----
1920788 05-18-15 09:42 aws-java-sdk-ec2-1.9.34.jar
503963 05-18-15 09:42 aws-java-sdk-core-1.9.34.jar
232771 01-19-15 09:24 commons-codec-1.6.jar
915096 01-19-15 09:24 jackson-databind-2.3.2.jar
252288 05-18-15 09:42 aws-java-sdk-kms-1.9.34.jar
62050 01-19-15 09:24 commons-logging-1.1.3.jar
282269 10-31-14 13:19 httpcore-4.3.2.jar
35058 01-19-15 09:24 jackson-annotations-2.3.0.jar
229998 05-29-15 12:28 jackson-core-2.5.3.jar
589289 01-19-15 09:24 joda-time-2.7.jar
562858 05-18-15 09:42 aws-java-sdk-s3-1.9.34.jar
590533 10-31-14 13:19 httpclient-4.3.5.jar
44854 06-12-15 19:22 elasticsearch-cloud-aws-2.0.0-SNAPSHOT.jar
-------- -------
6221815 13 files
```
A lot of those files are already distributed with elasticsearch itself so classes are available within the classloader.
We mark all es core dependencies as provided in plugins.
We also remove `groupId` as already defined in parent pom.
And we remove non needed licenses files as some jars are not included anymore in plugins.
Closes#11647.