Remove deprecated back

[fl0w]

#1114

Notice it being branched from fl0w:refactor-back, needs rebase post merge.

[codecov]

Codecov Report

Merging #1146 into master will increase coverage by <.01%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master    #1146      +/-   ##
==========================================
+ Coverage   99.73%   99.73%   +<.01%     
==========================================
  Files           5        5              
  Lines         374      375       +1     
==========================================
+ Hits          373      374       +1     
  Misses          1        1

Impacted Files	Coverage Δ
lib/context.js	96.96% <ø> (ø)	⬆️
lib/response.js	100% <100%> (ø)	⬆️

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[niftylettuce]

Any reason besides not having someone review this yet @fl0w to not merge? Would this go out in v3?

[fl0w]

This is branched off of #1115 which haven't been merged. #1115 is a semver minor fix for 2.x line and it should be merged first. This should only be merged when work on 3.x begins IMO.

I'm not sure why it never got merged, I wouldn't want to speculate.

[3imed-jaberi]

@jonathanong 👀