Implement Get and Set for Memcached.

Entirely untested code. Get is most definitely wrong for nonexistent keys.
Fixup Get() to possibly do something valid on unset keys.

Also implement GetQ/SetQ
Implement GetK, GetKQ
Makefile: Add missing phony targets to PHONY
Merge pull request #110 from cmaloney/mynde

Basics of Binary Memcache Protocol