added new methods to reduce even more the CSS

- Add Standard character encoding declaration @charset "UTF-8"; if missing (useful for Web FontIcons)
- Remove Quotes from url() properties since they are not needed (reduces 2 characters)
- Convert and Condense the 17 Standard Named Colors to HEX to save characters
- Condense the Font-Weight property to the integer version to save characters
- Added a method to reduce some Pixel values on properties by taking off 1px
- Added a method to reduce some Percentage values on properties by taking off 1%
- Added a " # lint:ok " to the imports so PyLint does not complain