Add progress bar for cli inference

[faroit]

What does this implement/fix? Explain your changes.

Any other comments?

[codecov]

Codecov Report

Merging #102 (8c40c46) into master (0f174b7) will increase coverage by 0.01%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master     #102      +/-   ##
==========================================
+ Coverage   76.99%   77.01%   +0.01%     
==========================================
  Files          18       18              
  Lines        1326     1327       +1     
==========================================
+ Hits         1021     1022       +1     
  Misses        305      305              

Impacted Files	Coverage Δ
openunmix/cli.py	86.15% <100.00%> (+0.21%)	⬆️

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