feat - add autoprefixer for postcss

[dacsang97]

#71

[danielcherubini]

oh awesome thanks!

[danielcherubini]

i'll get this in soon

[codecov]

Codecov Report

Merging #72 into master will increase coverage by 0.01%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master      #72      +/-   ##
==========================================
+ Coverage   91.05%   91.07%   +0.01%     
==========================================
  Files          11       11              
  Lines         447      448       +1     
==========================================
+ Hits          407      408       +1     
  Misses         40       40

Impacted Files	Coverage Δ
lib/renderer/process-style.js	55.26% <100%> (+1.2%)	⬆️

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[dacsang97]

@danielcherubini how can I pass tslint + eslint :)), eslint no need trailing command, but tslint (run in travis) required it.

[danielcherubini]

shouldn't be any eslint left... its all tslint now...

hmm sorry for that if you had a problem

[dacsang97]

@danielcherubini no problem, I passed 👍

[dacsang97]

@danielcherubini can u review this PR for me soon? :D