add support for go modules

[Atrox]

Hey,

I switched to go modules on my projects and because blackfriday is now supporting go modules too, I'm unable to use hermes because you are importing it with gopkg.in but blackfriday's module path is github.com.

To get the tests working, I switched from gometalinter to golangci-lint. gometalinter does not support go modules yet and it seems other popular projects are switching to golangci-lint too.

My current changes will only work for go 1.11+ projects, if you want we can check in the vendor directory generated by go mod vendor to support the versions below.

[codecov-io]

Codecov Report

Merging #44 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master      #44   +/-   ##
=======================================
  Coverage   98.45%   98.45%           
=======================================
  Files           3        3           
  Lines         907      907           
=======================================
  Hits          893      893           
  Misses          8        8           
  Partials        6        6

Impacted Files	Coverage Δ
hermes.go	77.77% <ø> (ø)	⬆️

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[matcornic]

Thanks for the PR, I will have to test everything next week.
Can you apply requested changed ?

Have a nice day :)

[maxekman]

Would love to see this merged, it's giving me a lot of trouble in its current state.

[Scapal]

Is there something blocking this merge?

For the moment I'm forced to do this in my go.mod:
replace github.com/matcornic/hermes v1.2.0 => github.com/Atrox/hermes v1.2.1-0.20181012135037-9d5eaf364c1b

[matcornic]

@Atrox @Scapal @maxekman Done 🎉