Add a Git .mailmap

...to make `git shortlog -es` look nicer.
whowas: Abort listing if 90% of sendq is in use.
Cope with rb_crypt() returning NULL.
Merge branch 'mailmap' of github.com:grawity/forks.charybdis
stats l: Don't care about away status.
UID/EUID: Check that the UID starts with the server's SID.

If not, the local link that sent the command is broken, as with
syntactically invalid UIDs.
UID/EUID: Add server's SID to invalid UID error message.