feat Add IsIP

[osintalex]

Here's a stab at IsIP.

I'm not sure how useful the netmask keyword argument is but thought I'd include it so you can see. Should be easy to take it out if you don't think it's a good idea.

[codecov]

Codecov Report

Merging #43 (004bf82) into main (593bccc) will not change coverage.
The diff coverage is 100.00%.

@@            Coverage Diff            @@
##              main       #43   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files           11        11           
  Lines          666       690   +24     
  Branches       167       174    +7     
=========================================
+ Hits           666       690   +24     

Impacted Files	Coverage Δ
dirty_equals/__init__.py	100.00% <100.00%> (ø)
dirty_equals/_other.py	100.00% <100.00%> (ø)

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[samuelcolvin]

otherwise LGTM.

[samuelcolvin]

let me know when this is ready to review.

[osintalex]

It's ready for review ☺️

[samuelcolvin]

thanks so much.