This commit fixes the implementation of the helper function SolidColor.
It now does correctly what it says: it sets the alpha bits to 0xFF.
Prior to this, the function would override part of the color due to an
incorrect shift.
This package adds back the Plain function from the old package text as
well as a new function called SolidColor that returns a new RGBA color
with the alpha bits maxed out.
These functions are there for convenience. They're also outside the
scope of the code generator and repository.
diamondburned