start work on type things

[CJ-Wright]

I'm not certain if this can go in. It certainly doesn't pass all of mypy at this point.
My hope is that it does help to clarify some of the types, especially when something is a package name or not.

[codecov]

Codecov Report

Merging #1218 into master will decrease coverage by 51.46%.
The diff coverage is 4.76%.

@@            Coverage Diff             @@
##           master   #1218       +/-   ##
==========================================
- Coverage   58.80%   7.33%   -51.47%     
==========================================
  Files          58      58               
  Lines        5578    5713      +135     
==========================================
- Hits         3280     419     -2861     
- Misses       2298    5294     +2996     

Impacted Files	Coverage Δ
conda_forge_tick/auto_tick.py	0.00% <0.00%> (ø)
conda_forge_tick/migrators/core.py	4.05% <0.00%> (-67.11%)	⬇️
conda_forge_tick/migrators/migration_yaml.py	0.00% <0.00%> (-56.83%)	⬇️
conda_forge_tick/utils.py	23.45% <50.00%> (-35.79%)	⬇️
conda_forge_tick/migrators/use_pip.py	0.00% <0.00%> (-96.30%)	⬇️
...a_forge_tick/migrators/conda_forge_yaml_cleanup.py	0.00% <0.00%> (-96.30%)	⬇️
tests/test_cross_compile.py	4.65% <0.00%> (-95.35%)	⬇️
conda_forge_tick/migrators/matplotlib_base.py	0.00% <0.00%> (-95.13%)	⬇️
conda_forge_tick/migrators/pip_check.py	0.00% <0.00%> (-94.96%)	⬇️
..._forge_tick/migrators/extra_jinj2a_keys_cleanup.py	0.00% <0.00%> (-94.45%)	⬇️
... and 41 more

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