fix: Use translate value in calculation (#72)

[thetravis]

This seems to fix the issue I've been having when using the directive in combination with angular2-draggable.

[codecov-io]

Codecov Report

Merging #76 into master will decrease coverage by 0.83%.
The diff coverage is 62.5%.

@@            Coverage Diff             @@
##           master      #76      +/-   ##
==========================================
- Coverage   95.45%   94.62%   -0.84%     
==========================================
  Files           4        4              
  Lines         308      316       +8     
  Branches       44       45       +1     
==========================================
+ Hits          294      299       +5     
- Misses          8       10       +2     
- Partials        6        7       +1

Impacted Files	Coverage Δ
src/resizable.directive.ts	94.89% <62.5%> (-0.98%)	⬇️

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[mattlewis92]

So sorry about the late reply on this one, I've not had much time for open source lately. I will cut a release shortly with this PR. Thanks for your contribution! 🎉

[thetravis]

I see you improved my solution :)

[mattlewis92]

Hope that was ok, you've already been waiting over a month and I didn't want to drag it out any longer by just reviewing instead of merging 😄

[thetravis]

Don't worry. I just made a dirty fix for my project as it needed to be fixed and I didn't care how at the moment. I'm rather new to web development also. My point was to address this issue and provide a solution of some sort :) Thank you, I think I can soon switch to back to the repo version.