debian/patches: Add...

debian/patches: Add 0005_release-keys-when-xfreerdp-is-unfocused-to-prevent-s.patch. Prevent Alt key from getting "stuck" with -grab-keyboard option when using Alt-Tab to switch between local X windows. Thanks to Petr Vorel <petr.vorel@gmail.com> for providing the patch. (Closes: #778650).