.functions: Add SNI support in `getcertnames`
Update URLs
.functions: Improve `getcertnames`
.gitconfig: Add alias to merge GitHub pull request

Ref. https://help.github.com/articles/checking-out-pull-requests-locally

Closes #422.
Brewfile: add some CTF tools

See https://github.com/ctfs/write-ups for more info.
Merge pull request #1 from mathiasbynens/master

sync with master