This converts the CMake license to a pure 3-clause OSI-approved BSD
License. We drop the previous license clause requiring modified
versions to be plainly marked. We also update the CMake copyright to
cover the full development time range.
Until now the VS 10 generator did no Windows command-line escaping and
just did XML escapes. This commit teaches the generator to use the same
command-line escape addition code used by other generators. The script
construction method cmLocalVisualStudioGenerator::ConstructScript need
not do XML escapes. Each VS generator version adds the XML escapes
necessary for that version.