Feature/add gomemcache

Add optional golang based gomemcache library. 
This library does not require libmemcached, and provides it's own pooling, but does not offer the level of control that gomc does. This library has NOT yet been fully load tested.

@bbangert || @kitcambridge r?
There's no error checking on this. It breaks immediately after, and any error from storeRec is ignored by line 332. Is this intentional? Or is this section supposed to be ignorable if it can't run, but the upper part of this function is critical enough to propagate the error?