fix: handle importing Sass partials in node_modules

[ryanoglesby08]

This fixes #86 by handling importing Sass partials from node_modules, so that something like this will work properly: @import ~foo/bar/partial where "partial" has the filename "_partial.scss".

[codecov]

Codecov Report

Merging #90 into master will decrease coverage by 0.19%.
The diff coverage is 90%.

@@            Coverage Diff            @@
##           master      #90     +/-   ##
=========================================
- Coverage   95.06%   94.87%   -0.2%     
=========================================
  Files           8        8             
  Lines         223      234     +11     
  Branches       81       81             
=========================================
+ Hits          212      222     +10     
- Misses         11       12      +1

Impacted Files	Coverage Δ
src/sass-loader.js	92% <90%> (-0.86%)	⬇️

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[ryanoglesby08]

Hi @egoist, is there anything else I can do here to move this along? Would like to upgrade to v1, but the bug that this fixes is blocking that for my project. Thanks for the great package by the way. Let me know how else I can help here.