Added unpack function
Updated position mixin to use unpack function on coordinates parameter
Updated position mixin to ignore falsy values
Add rem mixin for px fallback
Add Directional Property shorthands
Check if vals are the same
Update image-rendering mixing to conform with the last specification.

More information at [MDN](https://developer.mozilla.org/en-US/docs/Web/CSS/image-rendering) page.
Extract parts of directional-property into separate functions and add better directional collapsing
Add Code Climate badge to README
Updated hide-text mixin to comply with the new h5bp approach
Enable to custom triangle shape

Use $width and $height to custom triangle shape, if omit $height, this
mixin will generate code in the old way. The only downside is that
$width value should always be even number, otherwise triangle width
will be short 1px.
Add input button types as variable

To get all input button types, you must use interpolation on the variable:

#{$all-button-inputs}
#{$all-button-inputs-hover}
#{$all-button-inputs-focus}
#{$all-button-inputs-active}
Enable to custom triangle shape for up-left, up-right, down-left, down-right
Merge pull request #298 from hotmeteor/master

2009, 2011, and 2012 flexbox specs in unified mixins
Merge pull request #285 from emiliemarchand/hide_text_update

Updated hide-text mixin to comply with the new h5bp approach
Merge pull request #283 from mrb/master

Add Code Climate badge to README
Merge pull request #272 from thejameskyle/master

Directional Property Shorthands
Merge pull request #257 from thoughtbot/kf-rem

Add rem mixin with px fallback
Merge pull request #280 from alejandroiglesias/patch-1

Update image-rendering mixing to conform with the last specification.
Merge pull request #292 from audetpascale/master

Add input button types as variable