Removed Token for 'Label Reference'. Every Identifier is a Label Reference.
Added more tests for the Tokenizer.
Tokenizer now recognizes register references in the format <Register Type>:<Register Number>
Tokenizer now recognizes keywords in the language
Added tests for real numbers on the Tokenizer.
Tokenizer now recognizes real numbers.
Tokenizer now recognizes strings with escaped characters.
Added a bit of documentation to the Tokenizer function.