Some fixes and improvements

I made a fix for Gitolite:
- 233d2d4b fixed ssh-authkeys failing when the authorized_keys file contains commands or options for the keys already present in the file

I also made some improvements:
- 7e7dd91a allows to specify a custom Git location in Gitolite
- 7add7a53 rewrote update-gitweb-access-list in perl
- 7d4d34cc support multi-valued keys in config file

There's also 5566d5e6 when I merged code from sitaramc/gitolite@3e87a082

Pick any of those if you find they are interesting.