Add emacs-side caching of completions

Completion-at-point makes multiple calls, really slowing things
up. This change means that subsequent calls immediately return
the same result.
Use TryGetRecentResults for better caching

This should speed things up, but at the moment it doesn't work.
There never seem to be any recent results. Maybe a timestamp issue?
Record project load time and use in parse requests
Remove spurious text in docstring
Reenable Tooltip command and test briefly
First pass at tooltip support in elisp

Currently we just output it (badly formatted) using (message),
this will be updated to use some nice tooltips
Display tooltips properly. Add keybindings. Bump ver
Merge branch 'intellisense'