Updated README.md to specify Apache License and included extra text about proper usage.
Updated README.md to specify Apache License and included extra text about proper usage.

tad-iizuka/swift-sdk,tad-iizuka/swift-sdk,watson-developer-cloud/ios-sdk,watson-developer-cloud/ios-sdk,tad-iizuka/swift-sdk,watson-developer-cloud/ios-sdk,tad-iizuka/swift-sdk,tad-iizuka/swift-sdk,watson-developer-cloud/ios-sdk,watson-developer-cloud/ios-sdk