ExtUtils::ParseXS updated from blead

I've integrated the following patches from blead into
ExtUtils::ParseXS's mainline:

32691 on 2007/12/21 by stevep@stevep-kirk

	Clean up a warning with -Wwrite-strings that gets passed into every
	parsed XS file.

32223 on 2007/11/05 by nicholas@nicholas-saigo

	Allow (pedantically correct) C pre-processor comments in the code
	snippets of typemap files.

32209 on 2007/10/31 by nicholas@nicholas-pecuchet

	Now that ExtUtils::ParseXS requires 5.006, we can replace the foreach
	on keys and lookup in the loop with a foreach on values, as values is
	"now" an LVALUE iterator.

31983 on 2007/09/26 by rgs@counterfly

	API spelling patch, by Jerry D. Hedden


 -Ken

• ExtUtils::ParseXS updated from blead by Ken Williams