Remove swift_version file

Merge pull request #11 from dafurman/SwiftPackageManager-support

Package.swift: Added file to support Swift Package Manager

Update to Swift 5 with BUILD_LIBRARY_FOR_DISTRIBUTION = YES;

Update to Xcode11 and Swift 5

tag 1.7.0

update travis to Xcode 9.2

update travis to Xcode 9.2

Update readme and images

1.5.5

update travis