Bump version number to 0.1.3
Add -Wextra

I still have -Wno-unused-parameters in here because there's a bunch of
functions that just don't need their entire interface.  This found
some bugs, they were all just signed compare bugs where I had "int"s
that should have been "size_t"s.
Change indent rule

This now makes lines like

if () {

as opposed to

if ()
{

which I like better.  Essentially I agree with Linus's arguments here,
it's possible to have more stuff on a single page that way.