[FIXED JENKINS-19898] test base classes should not be linked to the junit implementation.

Changed the return type to be generic and not the junit specific CaseResult.

TestObject.fullName was used in the baseClasses jelly but this was only defined in the CaseResult so add an implementation to the base class such that people can continue to use the generic jelly in their cusomt test implementations.

Change-Id: I39fbff6621d7f20f9cebb210eea4f54a90f77375
[JENKINS-20534] Avoid usage of temporary file to write symlink.

Creating a symlink is an atomic operation, and additionally
usage of tmp file + rename performs very badly on NTFS file
system because of the way the rename is tracked in the $MFT.

In case symbolic links are not supported, we still fallback to
a regular file.
[FIXED JENKINS-21448] Report number of jobs in any container
Merge pull request #1097 from daniel-beck/all-items-stats

[FIXED JENKINS-21448] Report number of jobs in any container
Noting #1097
[FIXED JENKINS-21457] Replace description in error dialog instead of appending
Update changelog
Javadoc refinements for Describable.
fromdos
Merge commit '85e9df36efb7cd042ea8c8418fd80934db8aa9dd'
[maven-release-plugin] prepare release jenkins-1.549
[maven-release-plugin] prepare for next development iteration
updated changelog for release
updated changelog as a part of the release
merged back the RC branch
creating an RC branch
the trunk is toward 1.551-SNAPSHOT
Update credentials plugin
Noting that markup might be null.
[JENKINS-18282] Noting retroactively.