Fix nested tags inside of script tags.

Added some extra logic inside of the script tag specific piece of the parser to allow nested tags inside of script tags.  It used to infinite loop.

#115
this reads better but I'm still not understanding how this `AcceptAndMoveNext()` call could possibly accept a forward slash.  the `NextToken()` call updates `CurrentSymbol` but doesn't accept anything.  that call should leave the tokenizer in exactly the same state it was before the checks for '/' and text matching "script".  if it doesn't, something else is wrong (still).  therefore, the tokenizer should be looking at the '<' no matter what.