[misc] Optimized PNG images (reduced size)
[misc] Optimized GIF images (reduced size)
[FIXED JENKINS-16846] fix logic and add test

FilePath#moveAllChildrenTo faild,
when same name directory exist.

change Void to void, recursive_invoke is internal helper function.

thanks review by jglick
JENKINS-15178: Enabled log rotation on Mac OSX
Exclude the extraneous xmlpull and xpp3_min dependencies in jenkins-core.

The xpp3_min artifact causes a "JBAS015893: Encountered invalid class name" error on deployment in JBoss AS7 due to a malformed manifest in the artifact. The xpp3 artifact is extraneous since the xpp3 library is a direct dependency for jenkins-core. The xpp3 library replaces the xmlpull library.
Take subtasks into account when deciding to provision new nodes
[JENKINS-17510] Adding SecurityContextExecutorService - a wrapper to provide security context to each executor
Adding license and description to SecurityContextExecutorService
Changed eclipse default from tabs to spaces
Changing methods to correctly wrap the runnables and callables rather than the service itself
Adding basic test and rebasing
[JENKINS-17510] Adding SecurityContextExecutorService - a wrapper to provide security context to each executor
Adding license and description to SecurityContextExecutorService
Changed eclipse default from tabs to spaces
Changing methods to correctly wrap the runnables and callables rather than the service itself
Adding basic test and rebasing
Merge branch 'JENKINS-17510' of github.com:pmaccamp/jenkins into JENKINS-17510
Adding completed test that verifies threads obtain the correct security context
Adding additional test for runnables
Adding additional test for collection of callables