* implemented operation and param flags in the cli invoke cmd.
* reverted prev changes and added debug flag for compiling.
* change transactionType variable to Type, for package convention
* index support for arrays.
* implemented builtin (len) for the compiler.
* bumped version -> 0.35.0
* updated compiler README and changed invoke to testinvoke.
* implemented global variables.
* refactored imports + lots and lots of other sweet stuff + fix#28.
* Implemented the VM interop runtime API (GetTrigger, CheckWitness, ...)