feat(compressor): add Terser

[srod]

Close #427

[codecov]

Codecov Report

Merging #441 into develop will not change coverage.
The diff coverage is 100%.

@@          Coverage Diff           @@
##           develop   #441   +/-   ##
======================================
  Coverage      100%   100%           
======================================
  Files           22     23    +1     
  Lines          434    448   +14     
  Branches        82     86    +4     
======================================
+ Hits           434    448   +14

Impacted Files	Coverage Δ
lib/compress.js	100% <100%> (ø)	⬆️
lib/compressors/terser.js	100% <100%> (ø)

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