Adding unobtrusive type hinting

[otherJL0]

Adding simple type hints in independent functions as a first step to introduce type hints to the project

[CLAassistant]

All committers have signed the CLA.

[codecov]

Codecov Report

Merging #359 (5774e51) into master (071f1dc) will increase coverage by 0.00%.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##           master     #359   +/-   ##
=======================================
  Coverage   87.89%   87.90%           
=======================================
  Files          15       15           
  Lines        1495     1496    +1     
=======================================
+ Hits         1314     1315    +1     
  Misses        181      181           

Impacted Files	Coverage Δ
libtmux/common.py	86.93% <100.00%> (+0.06%)	⬆️

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[tony]

LGTM

This will make it into 0.11, which will release tomorrow

afterward 3.7 and 3.8 will be dropped

@otherJL0 this Saturday i will be adding type annotations and data structures #360. If you're around and have any ideas/feedback/PR sugggestions you'd like to contribute feel free

[tony]

@otherJL0 libtmux v0.13.0 has typings, if you'd like to try.