Update dependencies and fix new flow error in triangle.test.js

Fully deprecate returnUnit functionality and refactor return.

Make strict mode default when passing custom colors.

Enable bugfix:true in build and target explicit browser list

Default is now to look for a local font of the same family-name before downloading. Can be turned
off by passing null to localFonts.

BREAKING CHANGE: localFont will now be populated by default and may have unexpected behavior.

important helper for targeting specific rules in module returns for adding `!important`-level
specificity.

triangle now returns properties in a way that allows inherit to work by declaring an individual side
for the triangle color.

Allow the user to pass a default value to cssVar for when a variable is not found.

…n/max

Added an error case when the unit for to/fromSize is different than min/maxScreen. This was causing
bad calculations based on the differing scales.

BREAKING CHANGE: If you were using a mix of unit and unitless measure or working with different
units with similar scales (em/rem) you will now get an error where you may have been getting a
seemingly valid calculation.

fix #445