Removed some useless color transformations
Changed main function for minimal command-line usage (just simple minification operations, for now)
Removed unused function
Revert "Removed unused function"

This reverts commit 1821c00c6b04b97d80f9716c98717e185be67d52.
Re-enabled separate shorthand unfolding for correct duplicate pruning
Fixed bug causing background-position not to be folded
Implemented duplicate declaration pruning
Improved shorthand folding when component expressions are !important
Implemented font-weight optimization
Grouped font-weight and color optimizations in simple.ml
Minifier now checks oif input files exist
Removed some useless color minifications
Added --sort option
Merge branch 'minimal'