Add typing

[KianKhadempour]

This isn't 100% typed because the libraries that we depend on aren't 100% typed so I had to guess for some things. This caused me to find issue #97 (which you should check out). Apart from typing this PR:

• Standardizes default/failure values to None instead of some of them being False
• Uses dt instead of datetime in order to explicitly define timestamp as dt.datetime instead of making the type-hint the module, which was incorrect
• Changes abstract methods from simply returning to having ...
• Wraps mess["timestamp_ms"] in int() to explicitly show that it is an int (helpful for type-checking)
• Adds a few assert statements that make type-checking work
• Changes all formatted strings to f-strings (to please pylint)

[KianKhadempour]

Pytest errors are because | for Union was added in 3.10. I will fix that.

[KianKhadempour]

CodeCov patch is just complaining that I formatted the abstract methods "incorrectly" even though they are black defaults because if you do it the way I originally did them (when black complained) they count as covered code.

[codecov-commenter]

Codecov Report

Merging #98 (7ed3e91) into main (b908d2e) will decrease coverage by 0.16%. The diff coverage is 70.00%.

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@@            Coverage Diff             @@
##             main      #98      +/-   ##
==========================================
- Coverage   71.63%   71.48%   -0.16%     
==========================================
  Files           1        1              
  Lines         275      277       +2     
==========================================
+ Hits          197      198       +1     
- Misses         78       79       +1     

Flag	Coverage Δ
unittests	71.48% <70.00%> (-0.16%)	:arrow_down:

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
chatminer/chatparsers.py	71.48% <70.00%> (-0.16%)	:arrow_down:

[KianKhadempour]

Codecov Report

Merging #98 (289728f) into main (f7f34ff) will decrease coverage by 0.26%. The diff coverage is 70.73%.

❗ Your organization is not using the GitHub App Integration. As a result you may experience degraded service beginning May 15th. Please install the Github App Integration for your organization. Read more.

@@            Coverage Diff             @@
##             main      #98      +/-   ##
==========================================
- Coverage   71.63%   71.37%   -0.26%     
==========================================
  Files           1        1              
  Lines         275      276       +1     
==========================================
  Hits          197      197              
- Misses         78       79       +1     

Flag Coverage Δ
unittests 71.37% <70.73%> (-0.26%) ⬇️

Flags with carried forward coverage won't be shown. Click here to find out more. Impacted Files Coverage Δ
chatminer/chatparsers.py 71.37% <70.73%> (-0.26%) ⬇️

This is because I added a few variable types.

[joweich]

@BlueishTint commented and resolved all open discussions. Is there anything more you want to bring into this PR before merging?

[KianKhadempour]

Sorry I was gone for a while with no internet access. I think everything is good here.

[joweich]

@BlueishTint fyi, I will fix #99 and merge the fix into this PR. Then I'll merge your PR 👍🏼