Unifying simulation code

Currently the simulations used by soopercool are generated by many different scripts. We need to standardize the scripts/packages used for TF estimation sims, TF validation sims, CMB sims, FG sims, noise sims. This includes passing standardized theory CL files (including beams, where this simplifies things).

Currently, the status is:

• TF estimation sims for ISO are bandlimited at ell_max=650 with width 50
• A cleaned script for TF estimation sims has been added in #82
• A cleaned script for CMB-only sims has been added in #82
• CMB and FG sims can be produced by SOOPERSIMS in both map and alm format. The general TF validation script and the MC covariance script accept signal sims in both alm and map format.
• Noise sims generator scripts are outdated. TF validation / MC covariance scripts only accept maps, no alms. This relates to #40

We should decide on standard simulation code, ensure compatibility with core code, and add documentation.

Begin by reviewing the cleaned TF-estimation and CMB-only scripts added in #82, then compare SOOPERSIMS with the TF validation and MC covariance scripts. Determine a standard simulation path covering TF estimation, TF validation, CMB, foreground, and noise sims, with compatible map, alm, and theory CL inputs; document the resulting approach and its core-code compatibility.