Changes to LLDB Branch Management
https://lists.swift.org/pipermail/swift-dev/Week-of-Mon-20170206/004048.html
Library for structured editing of Swift syntax:
https://lists.swift.org/pipermail/swift-dev/Week-of-Mon-20170206/004066.html
SE-0146 implemented: https://github.com/apple/swift-evolution/pull/604/files
SE-0151 + 0152 accepted & implemented: https://github.com/apple/swift-evolution/pull/605
overflow/underflow
https://twitter.com/jckarter/status/831953187623952384