iOS SDK < 8 compatibility
Downgraded Estimote SDK from 2.1.5 to 2.1.0. That's the last version built with XCode 5. The newer versions link to `Metal` with requires iOS 8 SDK / XCode 6 to compile (which we don't have in AppBuilder just yet).
merged
Merge branch 'Telerik-Verified-Plugins-master'