Added new adopt function to CodeFragment

Adopt function simply adopts a single CodeFragment from any parent.
Tokens now default to empty strings instead of #

This was an old work-around to identify white-space. Default parameter
for aStringRepresentation in token constructors is much more sane.
Generalized argsAsVector and clean-up

Cleaned up the monstrous while-loop in ModifierParser with a much saner
TokenFind structure that can be applied elsewhere. Implementation of
this class required generalization of the argsAsVector function in
Utility.h to support other types than std::string. Added extra modifier
to modifier.txt example for checking in-array modifiers.