Missing translation in calibration flagging

[nicholebarry]

Looks like the last little bit of vis_calibration_flag.pro did not get translated to the python version, specifically:

IF Keyword_Set(no_frequency_flagging) THEN freq_use[*]=1
IF ~Keyword_Set(no_calibration_frequency_flagging) THEN obs_info.freq_use=freq_use

no_frequency_flagging is a common thing to set, it seems

[SkyWa7ch3r]

Looks like I've missed that no_frequency_flagging and it's used in a few functions, thankfully almost all those functions already import pyfhd_config so I should be able to add it as an option to the flagging group pretty easily. But I'll do it as a positive option i.e. flag_frequencies to avoid any double negatives which are confusing