[DOCS] Documentation tools

[Michael Scott]

I've added the Perl modules for the docs tools to lib/Parrot/IO and 
lib/Parrot/Docs. I've also added Pod-Simple (2.05) and Pod-Escapes 
(1.03) which they use.

Running

	perl tools/docs/write_docs.pl

should build the html tree in docs/html. I'd be interested to know of 
any problems encountered.

On the updating front, I finished examples and did the other *.c file 
directories (chartypes, encodings, io, pf, types).

Now I think I'll look at classes.

Mike