feat(routing): support range requests for static routes

[tipabu]

Summary of Changes

Add support for Range requests to static routes:

• Advertise support via Accept-Ranges
• Support both byte-range-spec and suffix-byte-range-spec forms
• Only support a single range per request
• Respond 416 when appropriate

Related Issues

Closes #1858

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[codecov[bot]]

Codecov Report

Merging #1959 (c49171a) into master (9ff7710) will not change coverage. The diff coverage is 100.00%.

@@            Coverage Diff            @@
##            master     #1959   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files           63        63           
  Lines         6624      6669   +45     
  Branches      1068      1079   +11     
=========================================
+ Hits          6624      6669   +45     

Impacted Files	Coverage Δ
falcon/request.py	100.00% <100.00%> (ø)
falcon/routing/static.py	100.00% <100.00%> (ø)

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[CaselIT]

thanks for the pr. I'll try to review shorlty

[tipabu]

Makes sense, sorry. Yeah, I'm coming more from gerrit, where ammending a commit and resubmitting is the norm. Good news is that the "force-pushed" text above links to https://github.com/falconry/falcon/compare/7e059b2f22a00406a8222fa8a60c8aad88293ade..a6fb3e0166f5a063deac1cb7bf256ff67b98b941 to just see the delta, but I think I've had problems with that in the past where github wouldn't know how to find the old commit.