[r21538]Win32:Apply \\ escape to all const paths

git-svn-id: svn+ssh://svn.code.sf.net/p/gramps/code/branches/maintenance/gramps40@21541 4ae1f11a-8b86-4847-b8af-ab372f36d1fd
[r21539]GrampsLocale: Restore setlocale, add GrampsLocale.encoding

encoding to replace translation().info()['encoding'] which isn't
the encoding we're looking for.

git-svn-id: svn+ssh://svn.code.sf.net/p/gramps/code/branches/maintenance/gramps40@21542 4ae1f11a-8b86-4847-b8af-ab372f36d1fd
[r21540]GrampsLocale: Add _win_bindtextdomain

Adapted from init_windows_gettext in Gramps3.
Libintl-8.dll must be on the path, just like all of the other C-library
dependencies.

git-svn-id: svn+ssh://svn.code.sf.net/p/gramps/code/branches/maintenance/gramps40@21543 4ae1f11a-8b86-4847-b8af-ab372f36d1fd