* Fixed bug where void functions cleaned up their mess multiple times
* Compiler improvements
* Fixed Neo APIs naming convention
* Added NOP after syscall for matching AVM files with neo-python.
Imported from CityOfZion/neo-storm (f93a28ef87d272a74f821d45ae0c6735a8c610be).
* Draft of iterator and enumerator
* Added iterator API to the syscall mapping
* Added draft of the enumerator.go file
* Added enumerator interop API.
* Updated the changelog
Imported from CityOfZion/neo-storm (156093318b8612e810965bb1ea26e1babfb46cdd).
* new mapping for interop api
* Fixed interop API mapping + added missing apis
* added engine apis
Imported from CityOfZion/neo-storm (ec5e6c8e2b587704a1e071e83b633d2d3a235300).
