skip a test if HTML::TreeBuilder is not installed
add metafiles
compilation problems

* forgot aTHX_ in a few places
* for(int i = 0; ...) -> int i; for(i=0;...)
bump version, 0.11
replace MUTABLE_*V(x) with explicit casting

This set of macroses was introduced in perl 5.11
and at this moment is not supported by Devel::PPPort[1].
Not going to shave this yak for two uses of the macro.

[1] https://rt.cpan.org/Public/Bug/Display.html?id=80476
bump version, 0.12
Merge remote-tracking branch 'origin/master'

Conflicts:
	META.json
	META.yml
	t/tree.t
update meta