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>

cgitrc.5.txt

@@ -120,6 +120,10 @@ enable-index-links::
 	each repo in the repository index (specifically, to the "summary",
 	"commit" and "tree" pages). Default value: "0".
 
+enable-index-owner::
+	Flag which, when set to "1", will make cgit display the owner of
+	each repo in the repository index. Default value: "1".
+
 enable-log-filecount::
 	Flag which, when set to "1", will make cgit print the number of
 	modified files for each commit on the repository log page. Default