[FIXED JENKINS-24341] - Check if the project can be disabled before the disabling

The change call the AbstractProject::supportsMakeDisabled() before calling AbstractProject::makeDisabled()

Signed-off-by: Oleg Nenashev <o.v.nenashev@gmail.com>
Remove jenkins svnkit in favor of default svnkit library.
Fixed unit tests where resulting revision string contains a lower case A.
Fixed ClassCastException with DefaultAuthenticationManager.
Proper fix for DefaultSVNAuthenticationManager. Currently the default version in svnkit ignores any added authentication methods other than the three default items. This fix ignores any authentications that are stored on disk or persisted to memory. Since we create our own authentication, we should ignore the default items and use our own instead.
If there is an already existing svnserve instance running, fail the build.
Fixed test unit.
Use assertLogContains instead of manually scanning logs.
Fixed license headers and added COPYING file with license. Moved svnkit specific elements in to another package.
Renamed ISVNAuthenticationManager to a simpler name.
Merge pull request #92 from synopsys-arc-oss/JENKINS-24341

[FIXED JENKINS-24341] - Check if the project can be disabled before the disabling
Make form validation work when configured on a non-AbstractProject, like a workflow job.
If default svnserve port is already used, pick a random port.
Merge remote-tracking branch 'upstream/master' into removesvnkit
Fixed compilation issue. Use Jenkins internal authentication manager instead of the svnkit interface.
Change DefaultAuthenticationManager to be SVNAuthenticationManager which uses credentials for authentication instead of .subversion directory.
Remove unused interface.
[maven-release-plugin] prepare release subversion-2.5-beta-4
[maven-release-plugin] prepare for next development iteration
Make SVNRevisionState public

Required so another plugin can retrieve the built revision. Typical use case is svnmerge-plugin which has to merge built revision to upstream branch