git-svn-id: http://root.cern.ch/svn/root/trunk@42310 27541ba8-7e3a-0410-8455-c3a389f83636

changes needed to implement XROOTD as external package together with
the alien and monalisa plugins. I have also introduced a new option
(builtin_xrootd) to build XROOD together with ROOT.


git-svn-id: http://root.cern.ch/svn/root/trunk@42100 27541ba8-7e3a-0410-8455-c3a389f83636

Introduce alternative cmake based build system. Cmake is especially convenient
for building on Windows, as it can produce VC projects or nmake files and 
does not require cygwin to be installed. In addition on OSX Xcode projects
can be generated.


git-svn-id: http://root.cern.ch/svn/root/trunk@39463 27541ba8-7e3a-0410-8455-c3a389f83636