Added basic test for the Checkstyle-XML-Api
testing the checkstyle-tabs
[JENKINS-22788] Automate gerrit rev.; need to automate g-t server start.
Merge branch 'master' into checkstyle_xml_api

Conflicts:
	pom.xml
	src/main/java/org/jenkinsci/test/acceptance/plugins/checkstyle/CheckstyleAction.java
	src/test/java/plugins/CheckstylePluginTest.java
Running gitplugin tests against docker container
Basic tests checking the api of each findbugs, pmd and checkstyle as well als basic checks for the detail build tabs
Merge branch 'master' of https://github.com/itgkarl/acceptance-test-harness
[JENKINS-22788] Automate gerrit-trigger server start; next: gerrit check
[JENKINS-22788] Automate gerrit review check; new usage; left: proxy cfg
fixed pom xml indentation
indented expected api-xml-files and added comment regarding whitespaces. Changed visibility of a helper method to private
Added JavaDoc for tests.
Reverted file permissions
Merge branch 'checkstyle_xml_api' of https://github.com/jenkins-acceptance-test-group/acceptance-test-harness
[FIXED JENKINS-22788] Optional env. proxy support; slight usage change.
Running gitplugin tests against docker container
@WithPlugin now supports specific versions.
example: @WithPlugin("scriptler@2.6")
Atm only works with plugins not already existing.
Merge branch 'gitplugin/docker' of https://github.com/tomasulo/acceptance-test-harness
seperated sha1sum branch
added fix detecting change in dockerfile and trigger rebuild of image