Swift 4 Support.
This release minimally requires use of the swift-3.1.1-RELEASE toolchain or the swift-4.0.0-RELEASE toolchain which is recommended.
- Compatible with Xcode 9.0 (9A235) General Release or higher using one of the above toolchains.
- On Linux this release support OpenSSL 1.0.x only.
- Corrected some issues with SSL error handling on Linux. PR #42.
- Added framework target to Xcode project, issue #44.
- Added Cathage support. #44. #45.
- Remove build on Xcode 8.3.
- CI updates.
- Changes to adapt to Swift 4.1.