[string]
updated for c++11
[General]
changed all pointers to check against nullptr instead of NULL
changed error handling to use exceptions.
[tstring]
added a post increment ++ operator for getting multiple tokens in a row (testing)
added template versions of the to_???() functions.
started work on an iterator for the tokens that doesn't involve using a vector etc.. as we do now. (all commented out atm)
added a template append_number() function to allow adding any number type easily.
changed the numeric += operator to use the append_number() function when templates are enabled.
removed some old commented code.