getlantern/lantern#1969 Not returning any friends until load succeeds

Closes #1969 

I should note that I tested this to make sure that the happy path works (bring up friends dialog, add friend, reject friend).  The only way that I was able to reproduce the bug itself was by messing with the logic on the client that distinguishes between a known friend and a new suggestion.
@myleshorton I took this out because it actually has the effect of kicking off another load, which we don't want.  There's also no need, since the friendsLoaded future is set to null.