From Gerri:

some small mods that prepare the ground for the new PROOF patch:
- TMessage.h, TMonitor.h: add friendship to new socket classes
- TSemaphose: support relative timeout in Wait()
- TUrl: in GetUrl() add option to also get default port numbers as part
        of the url.


git-svn-id: http://root.cern.ch/svn/root/trunk@13588 27541ba8-7e3a-0410-8455-c3a389f83636