js: Use defer/async in e-mail deobfuscator

We use both defer and async to gain wider browser support[0], since this
is the only JS on the page, it doesn't matter to us which of these is
used.

0: http://stackoverflow.com/a/10731231/945780
ssh: Add comment to public SSH key.

This should make it easier to identify when adding to an already huge
authorized_keys file.