Contra-directional coupler coupled-mode theory + TMM + Lumerical simulator flow

Added contra-DC Lumerical simulation flow

Initial release

Core functions added:
-calibrate
-baseline_correction
-cutback
-to_s_params
-download_response

Solvers and simulators added:
-Bragg CMT
-Rings system desinger

Framework release

Merge branch 'master' of https://github.com/mustafacc/SiEPIC_Photonic…

…s_Library