Simple integration with auto-complete.el

To use. Do the following:

(setq rtags-completion-enabled t)
(setq rtags-ac-completion-enabled t)

reevaluate rtags.el

start rdm like so:
rdm -a 5

 (or some other number larger than 0, this is the number of cached
 translation units so it will use some memory).

And it should just do its thing.
Remove this.
Ignore this.