Support Windows for resolve path

[gucong3000]

No description provided.

[sindresorhus]

Is there any test failing on Windows before this change? If not, would you mind adding a test for this?

[gucong3000]

Is there any test failing on Windows before this change?

Yes.

title: should filter relative paths that leave current directory tree
https://github.com/sindresorhus/gulp-filter/blob/master/test.js#L164

[gucong3000]

  2) filter() should filter relative paths that leave current directory tree:

      Uncaught AssertionError [ERR_ASSERTION]: 0 == 1
      + expected - actual

      -0
      +1

      at StreamFilter.stream.on (test.js:174:11)
      at endReadableNT (node_modules\streamfilter\node_modules\readable-stream\lib\_stream_readable.js:992:12)
      at _combinedTickCallback (internal/process/next_tick.js:138:11)
      at process._tickCallback (internal/process/next_tick.js:180:9)