0.8.0-beta.1

This release is meant for use with Xcode 7.1 and Swift 2.1.

Improved

• Update to Swift 2 and ReactiveCocoa v4.0-alpha.3 (#29, #35, #36, #37). Thanks @mattprowse and @ikesyo!

Thank you to @mdiep and @NachoSoto for reviewing PRs!