bottles: use String#[] instead of "captures.first rescue nil"
git: use opt_prefix for pcre
git: detect presence of perl's ExtUtils::MakeMaker
gnupg2 2.0.20

Signed-off-by: Jack Nagel <jacknagel@gmail.com>
gpg-agent 2.0.20

Closes #20235.

Signed-off-by: Jack Nagel <jacknagel@gmail.com>
gnupg2: refresh patch