v0.7.1 Release

This is a patch release of v0.7.0 that fixes #504 (via cdd81d2). The patch addresses a race condition where multiple Netty transports can be created by the same builder, resulting in an unsharable handler being added to multiple Netty pipelines. In addition, better error handling has been added to the bootstrap of TLS pipelines in order to detect errors that occur early on in protocol negotiation that may have previously been missed.