Added failing test for brpoplpush command
Fix brpoplpush timeout reply handling
Checks for tv.tv_usec as well as tv.tv_sec when setting the read
timeout option on our socket.  We were actually ignoring timeouts
< 1 second because of this.

Nice catch by @xiaoyjy

Fixes #286
Merge pull request #272 from pepve/brpoplpush

Thanks for the pull, merging.