feat: URL validation classes 'Url' and 'ReqUrl'

[rafamizes]

Closes #96

[codecov]

Codecov Report

Merging #159 (2aaa8c0) into master (c2280cb) will not change coverage.
The diff coverage is 100.00%.

@@            Coverage Diff            @@
##            master      #159   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files           47        49    +2     
  Lines          435       442    +7     
=========================================
+ Hits           435       442    +7     

Impacted Files	Coverage Δ
lib/src/net/req_url.dart	100.00% <100.00%> (ø)
lib/src/net/url.dart	100.00% <100.00%> (ø)

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[rafamizes]

@rultor merge it.

[rultor]

@rultor merge it.

@rafamizes OK, I'll try to merge now. You can check the progress of the merge here

[rultor]

@rultor merge it.

@rafamizes Done! FYI, the full log is here (took me 5min)