Merge pull request spotify#94 from themackworth/release_1_1_1

Prepare for 1.1.1 release

Merge pull request spotify#83 from 8W9aG/release-1.1.0

Release 1.1.0

Merge pull request spotify#54 from iOSCowboy/release-1.0.0

Podspec: Specify in which platform SPTPersistentCache is used