Removing old ParameterizedGateInstruction, modifying Instruction concept to provide 0 to N parameters, updated Rz and Measure

Starting work on parameterized kernels. Cleaned up json persistence with JsonVisitor. Cleaned up Program.hpp

Setting up CMake build to add xacc-config.cmake to install prefix, enabling apps building off XACC to easily integrate into cmake builds

Major repository restructure. quantum is now the quantum runtime package, moved rigetti, simple acc, and scaffold to impls dir