po: go back to storing the .pot file in git

po: go back to storing the .pot file in git

To integrate with weblate the only practical option currently is to
store the .pot file in git. This is required so that it can add new
languages by cloning the .pot file. It also enables weblate to run
msgmerge on the languages whenever pulling in new changes from git.

The pot file will have to be the full content including the source
locations, so this is going to result in unpleasant diffs when it
is updated periodically.

Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>