Bug 1096608: minor fixes to run toplevel::slave::releng on windows; r=markco

 * no display manager on windows
 * wget, hg are from MozillaBuild
 * create /builds/slave as c:/builds/moz2_slave (ugh)
 * put more stuff in ${dirs::etc::base}
 * fix up filemodes
Merge default -> production

--HG--
branch : production