Make "owner" column on index page configurable

This is not really needed for personal sites where all repos belong to
the same person. Since it is pretty useful for shared sites however, it
should be configurable.

Signed-off-by: Florian Pritz <bluewind@xinu.at>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
ssdiff: correctly manage tab expansion

Previously, replace_tabs("foo\tbar") would become "        foobar".

Signed-off-by: Julius Plenz <plenz@cis.fu-berlin.de>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>