Add highlight faces

Added some faces for the user to use for highlights, so they don't
have to define their own right away.
Fix `mu-highlight'

Used to highlight the entire line on which a match was found, instead
of just the match.
Don't send "connect" command when password is empty

Fixed conditional in (when (mu-world-password world) ...) to check
that the password is also not an empty string.
Fix `mu-highlight'

Non-matches would clear fontification of previous matches.
Bind TAB to `dabbrev-expand'
Remove leftover file from debugging

highlight.org should have been deleted when the highlights branch was
merged.
Fix `mu-highlight'

Highlights are now applied *after* `ansi-color-apply', so control
characters don't break highlight-regexp matching.
Fix `require's

* Load ansi-color with `require' instead of `load'
* `mu-highlight' uses `map' from cl, so `require' that.
Don't split frame

Use `switch-to-buffer' instead of `pop-to-buffer' for switching to the
server buffer.  The old behaviour was leftover from when a separate
input buffer was used.
Fix highlights

*Actually* run `mu-highlight' after `ansi-color-apply'.
Merge branch 'master' into login-regexps
Fill in `mu-login'

Filled in `mu-login' case where called as an output-filter function.
Still won't work because it depends on the current world being bound
to a (buffer-local) variable.
Use a separate highlights list for each world

`mu-highlights' is now an alist of highlights for each world, where
the highlights for each world are in the same format as before.
Merge branch 'master' into login-regexps
Use login-prompt regexps

When connecting to a server, if the given world specifies either a
char- or password-prompt regexp, send the character name and password
when a line matching those is received, instead of just send int the
name and password via the "connect" command, which doesn't work on all
servers.