New phase generation template

[andrerenard]

Base code for the new beamforming phase generation.

TODO:

• Add new UTC to UT1 endpoint - Moved to Added the new compute_phases function #1031
• Confirm element/frequency array indices
• Phase copy functions for HSA/OpenCL
• Add array element positions file for CHIME - Move to Added the new compute_phases function #1031
• Refactor beam_coord struct? -> Decided against this change

[andrerenard]

@Sengate @VishwangiShah312 FYI: This is the base code for where you will be adding your new beamformer phase generation code. This code is not yet done, but most of the basics are in place. The main area you will be adding code to are TCPhaseUpdate::compute_phases() and FloatPhaseUpdate::compute_phases() respectively.

This code is not completely done, but I'm hoping to have it finished over the next two weeks. If you want to get started with integrating your code as I finish this, you can branch off this branch (ar/gains_stage) and start adding your new functions.