Change `rem`s in media queries to `em`s

http://stackoverflow.com/questions/12201003/media-queries-with-rem-units-in-chrome
Merge pull request #4 from thomasdobber/patch-1

Change `rem`s in media queries to `em`s
Updating for publish
Initial publish of flexboxgrid
Better formatting of README
Formatting README
Fixing links
Updating to use calc for IE11 rounding differences
Updating to use calc for IE11 rounding differences.
Updating download link
Updating dev dependencies
Updating autoprefixer
Updating to add reponsive modifiers to alignment, distribution, and reordering.
Updating api to add responsive modifiers to alignment, distribution, and reordering.
Updating download link
Updating built artifactes
Updating class names. Removing gutters to fix IE issues.
Updating class names and removing gutters
Updating inheritance
Fixing rounding issues for IE10+