allow gitolite to be used when the users already have real IDs

Fedora (for example) runs like this:

  * each user has his own userid and login
  * his/her ~/.ssh/authkeys file (containing only his/her key) has a
    "command=" clause invoking just "gl-auth-command"
  * trusted users have "gl-auth-command -s" meaning they can get a shell if
    they want to

As a result, there is no specific $HOME where you can look for
.gitolite.rc.  Hence this patch

----

Side note: in addition, Fedora may have one or more of the following
characteristics (writing them here for convenience; they're not directly
relevant to this patch):

  * actual git repos are under "git" (or some such), and include the chmod g+s
    (git init --shared) unix perms tricks for shared access

  * but since they're coming through gl-auth, branch-level acls are in effect

  * the gitolite config file is generated from some database and compiled (all
    via cron)

  * they keydir/ is empty; in fact they probably don't use the admin repo at
    all, AFAIK

src/gitolite.pm

@@ -265,8 +265,15 @@ sub where_is_rc
 
     return if $ENV{GL_RC};
 
-    my $glrc = $ENV{HOME} . "/.gitolite.rc";
+    # Fedora doesn't actually have a "hosting user" at all (yeah -- bet you
-    $ENV{GL_RC} = $glrc if (-f $glrc);
+    # didn't know gitolite was *that* flexible!), so there's no fixed $HOME,
+    # and they prefer to keep their RC file in /etc/gitolite.
+    for my $glrc ( $ENV{HOME} . "/.gitolite.rc", "/etc/gitolite/gitolite.rc" ) {
+        if (-f $glrc) {
+            $ENV{GL_RC} = $glrc;
+            last;
+        }
+    }
 }
 
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