Update travis config to use latest wkhtmltopdf RC

[0xhaven]

We needed to do this to avoid this issue: wkhtmltopdf/wkhtmltopdf#3001 based on @ashkulz suggestion.

[codecov-io]

Codecov Report

Merging #16 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master      #16   +/-   ##
=======================================
  Coverage   91.33%   91.33%           
=======================================
  Files           3        3           
  Lines         450      450           
=======================================
  Hits          411      411           
  Misses         25       25           
  Partials       14       14

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[SebastiaanKlippert]

Thanks for the quick update!

[ashkulz]

Please note that the rc builds will be removed from the current location after the final release (which will be hosted at Github).

[SebastiaanKlippert]

Thanks for the reminder @ashkulz
I will update after the latest release.

[ashkulz]

0.12.5 has been released and -rc builds have been removed, please take updated URL from https://wkhtmltopdf.org/downloads.html#stable

[SebastiaanKlippert]

Thanks, been looking at your releases and waiting for the builds

[ashkulz]

Yeah, had to redo them because of a limitation in Github. It takes ~16 hours to build for all platforms, so it took time.