CocoaPods and build.sh updates

- Updated podspec to support both iOS & OSX
- `clean` now removes all non git-versioned files (except `core/`)
- added `browser` target
- added `deploy` target
- added `pod-deploy` target
agree with @kneth.
clean means remove all generated files in my perception. Nothing of value can be lost.
git-clean is a different beast altogether wiping any files I might have added or left from switching between branches.