Added a new rule and improved options validators

0.0.5

Bump version

Improved message reporting for colors nested into complex values

Example:

border: 1px solid rgba(0, 0, 0, 0.15);

Now reports Illegal use of a literal 'rgba(0, 0, 0, 0.15)' with property 'border'. Expected a variable. instead of Illegal use of a literal '1px solid rgba(0, 0, 0, 0.15)' with property 'border'. Expected a variable.

0.0.1

Inital release