* [swift] make some small improvements
* [swift][client] revert model to use allVars
* PostProcessModelProperty with allVars
* PostProcessModelProperty with vars
* [swift] improve objc interoperability
* [swift] fix swift4 for CI to pass
* [swift] improve objc interoperability
* [swift] improve objc interoperability
* Swift - try to fix build
* [swift] remove pods from git
* Convert not string enum default value to string by toString.
* Add some test cases for enum's default value.
* Convert string default value to enum var name format.
* sync master, update samples