+ obtain the msdos version on startup

git-svn-id: http://svn.freepascal.org/svn/fpc/trunk@24574 3ad0048d-3df7-0310-abae-a5850022a9f2
- rm debug writeln committed by accident

git-svn-id: http://svn.freepascal.org/svn/fpc/trunk@24575 3ad0048d-3df7-0310-abae-a5850022a9f2
+ added dos version check in GetProgramName

git-svn-id: http://svn.freepascal.org/svn/fpc/trunk@24576 3ad0048d-3df7-0310-abae-a5850022a9f2