So far, errors just killed the whole program and in case of an error
inside of libgit it would be totally uncatchable. This patch makes
Git.pm throw standard Perl exceptions instead. In the future we might
subclass Error to Git::Error or something but for now Error::Simple
is more than enough.
Signed-off-by: Petr Baudis <pasky@suse.cz> Signed-off-by: Junio C Hamano <junkio@cox.net>