clarifying the if statement when a memcache.Get comes up empty inside GetMulti

Conflicts:
	goon.go
Embedding the struct and bumping up the memcache timeout value for the tests that don't want memcache to timeout.
adjusting default memcache.Get() timeout value
Thanks @xStrom - https://github.com/mjibson/goon/pull/21#issuecomment-32904674
Merge branch 'memcachevariancetesting' into memcachevariance

Conflicts:
	goon.go
	goon_test.go
	timeout_testing.go