GitLab

Too many docker users are caught out by the default location for the
app.ini file being environment dependent so that when they docker exec
into the container the gitea commands do not work properly and require
additional -c arguments to correctly pick up the configuration.

This PR simply shadows the gitea binary using variants of the FHS
compatible script to make the command gitea have the default locations
by default.

Fix #14468
Reference #17497
Reference #12082
Reference #8941
... amongst others ...
Replace #17501
Signed-off-by: Andrew Thornton <art27@cantab.net>