waylandloginmanager: fix reloading of the active session pid, so that if it's recovered from a crashed instance, it won't be overwritten

git-svn-id: https://rebeccablackos.svn.sourceforge.net/svnroot/rebeccablackos@2959 56e3d1a8-0179-4092-b3e2-9fbbcda0c0a9
No need to install kde4 development headers for kde5

git-svn-id: https://rebeccablackos.svn.sourceforge.net/svnroot/rebeccablackos@2960 56e3d1a8-0179-4092-b3e2-9fbbcda0c0a9
document the sessiondata file

git-svn-id: https://rebeccablackos.svn.sourceforge.net/svnroot/rebeccablackos@2961 56e3d1a8-0179-4092-b3e2-9fbbcda0c0a9
document control files

git-svn-id: https://rebeccablackos.svn.sourceforge.net/svnroot/rebeccablackos@2962 56e3d1a8-0179-4092-b3e2-9fbbcda0c0a9
Document the build_core control files

git-svn-id: https://rebeccablackos.svn.sourceforge.net/svnroot/rebeccablackos@2963 56e3d1a8-0179-4092-b3e2-9fbbcda0c0a9