Added RGB, RGBA, Hex Alpha, Hex Short Alpha input formats.
Removed private $color variable (the input color).
Added private color channel variables.
Set color channels for each method.
Set color channels as ints for RGB, and float for alpha.
Added output methods for hex, cssHex, shorthandHex and cssShorthandHex.
Added Web Safe color output.
Added new output formats: Hex with alpha, Shorthand Hex with alpha.
Removed non-css hex output formats. Made CSS default hex output format.