Standardize discovery module

[AdamTheisen]

We need to standardize the discovery module. I think it would be better if we remove the "get_" from every file and leave as "neon", "arm", etc... We then should update the functions to remove "get".

[zssherman]

@AdamTheisen So rename the modules and then for those functions that don't start with download, but instead with get, change those to download_blank as well?

[AdamTheisen]

@zssherman I'm thinking of removing the "get_" from the file name as the main part. In looking at the function names, we have to be careful and maybe we make it a standard that if it actually downloads a file, we have "download_" at the front instead of "get_" but if all it's doing but if it's returning a DataSet then keep as "get_". Open to thoughts/opinions hear though

Looking at IO, we just have mpl, neon, armfiles (which we might want to rename as well to just arm), icartt, etc... so just trying to be consistent in discovery and with the rest of ACT

[AdamTheisen]

I was also thinking that we might want to follow similar suit to the renaming of HistogramDisplay to DistributionDisplay and copy the codes over to the new name, put in a deprecation warning and then remove in the next major release.

[zssherman]

@AdamTheisen Yeah I think that's a good path forward

[zssherman]

Deprecation warning i think is a good idea as well to warn people. We could start with one submodule at a time, can change the discover module and have the warning in the original code and then add the duplicates of each module with the renamed file and functions (if functions need renaming). And do renaming of the io stuff later on. The docstrings in the original code might need to be removed so were still not generating the old code, and have the docs build the new stuff (this part im unsure though to be honest)

[zssherman]

But I think i get what you mean as well on the function naming, as airnow, its just getting the information from the website and is not actually downloading anything

[AdamTheisen]

The base for this is in #724 but we will need to update when we do the V2.0.0 release to remove the old files and make sure the new ones are in init.py