New getrefr module

[standage]

This update introduces a new module for downloading the human reference genome into a dedicated "package data" directory. This replaces the current sub-optimal behavior of requiring the user to have a specifically-named reference genome file in the current working directory.

By default mhpl8r getrefr will download the genome directly from UCSC, but it also supports "installing" a previously downloaded copy from a local file path.

[codecov-io]

Codecov Report

Merging #30 into master will decrease coverage by 5.18%.
The diff coverage is 43.54%.

@@            Coverage Diff             @@
##           master      #30      +/-   ##
==========================================
- Coverage   98.16%   92.97%   -5.19%     
==========================================
  Files          17       19       +2     
  Lines         600      655      +55     
  Branches      114      118       +4     
==========================================
+ Hits          589      609      +20     
- Misses          4       39      +35     
  Partials        7        7

Impacted Files	Coverage Δ
microhapulator/cli/sim.py	100% <ø> (ø)	⬆️
microhapulator/cli/mixture.py	100% <ø> (ø)	⬆️
microhapulator/cli/refr.py	100% <ø> (ø)	⬆️
microhapulator/refr.py	100% <100%> (ø)	⬆️
microhapulator/mixture.py	100% <100%> (ø)	⬆️
microhapulator/sim.py	97.5% <100%> (ø)	⬆️
microhapulator/cli/__init__.py	93.75% <100%> (+0.2%)	⬆️
microhapulator/__init__.py	100% <100%> (ø)	⬆️
microhapulator/cli/getrefr.py	100% <100%> (ø)
microhapulator/getrefr.py	23.91% <23.91%> (ø)
... and 2 more

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