Use -C flag to to call a sub-make to another directory
Removed useless exit call because the `-e` shell flags imply
Replaced from `$(srcdir)/..` to `$(top_srcdir)`
Added CYGPATH_W to convert proper path
Fixed string quoting on the postintall script
Added GPG macro to custumize gpg program
Fixed `sys.path`
Fixed VERSION regeneration
Fixed WS
Fixed installcheck target
Fixed when DESTDIR is empty it install python lib to the current path