Use `self.pm` to avoid multiple borrows in an easier way
More robust `make clean`
Fix test - no wonder why the popped handle was not removed on destroy
before destroying the Select object.
Refer to context in socket
Fixed #13, implemented inproc protocol
Fixed #21, allow socket objects be sent to different tasks
Fixed #22, refactor to remove peer.rs
Refs #12, some more docs
Update README to refer to the docs
Added travis build status icon in README
Replace crate_id with crate_name
Merge pull request #3 from zeromq/master

Update with upstream