GitLab

* Add mvn asciidoctor commands
* Fix formatting in mvn plugin

Add "-DgroupId= -DartifactId= -Dversion= -Dpackaging=jar -Dfile=" to options for
"install:install-file" for when you need install a local jar file.

Closes #5376.

* Adds -DskipITs to auto completion list

* Adds integration test completion

* add 'mvn clean install -DskipTests --offline' to speed up maven compile

* update maven plugin README

add "-Dmaven.test.failure.ignore=true" .
This option will not ignore all tests but ignore the failures when run tests.

See http://maven.apache.org/surefire/maven-surefire-plugin/test-mojo.html#testFailureIgnore

Setting the locale to C will stabilize sed, so it won't stop processing
the mvn output when it encounters invalid characters (like binary data)

This makes it also more viable to add the `alias mvn='mvn-color`, as
the coloring is less obtrusive, and there won't be any issues with sed
breaking because of an invalid character inside the stream

for other (than Java) JVM languages