Fix upcase operator inside a string

Signed-off-by: Gustavo L. de M. Chaves <gnustavo@cpan.org>
Delay computation of Gerrit's URL

We compute the URL only when we need to use it. Also, we don't require
anymore that all configuration be set. There are subcommands that
don't require all configuration.

Signed-off-by: Gustavo L. de M. Chaves <gnustavo@cpan.org>