Merge pull request #314 from AliSoftware/feature/spm-support

Adding Swift Package Manager Support

Merge branch 'master' into master

Merge pull request #308 from AliSoftware/release/8.0.0

Release Prep for 8.0.0

Merge pull request #295 from jeffctown/feature/Swift4Support

Updating for swift 4.x and Xcode 10.1

Merge pull request #303 from AliSoftware/release/6.2.0

Preparing for release.

Fix min version watchos