Control WORDS written in Forth

One of the things I would like to do in future is allow this implementation of 'Forth' to compile, either natively or to a byte code.

One of the things that stands in the way of this is the sheer amount of C++-based words. To this end I have converted the control structures (If/else/then/do/loop/+loop/being/while/repeat/again) into Forth.

When reading the Forth for these, bare in mind that these words are all immediate words. They get run inside a colon definition, and usually add words to the words being compiled.