Enabling conda install

Created by: AlecThomson

Hey @lh-astro,

This PR enables the stand-alone installation of frocc using a conda enviroment. Installation can now be done by cloning the repo and doing conda env create. This creates an environment also called frocc which (hopefully) contains all the required dependencies. In a way, this removes the need for a singularity container. Of course, this package could still be containerised, but this is no longer necessary.

I've also tidied up some lingering 'meerkat-pol' references in the code.

I'm testing right now, and all seems to be ok. But, I can't be sure that some functionality isn't broken, so it'd be great to do further tests.

I hope this is useful, and within your envisioned development scope!

Cheers, Alec