compound document: 1st version getting the content-type of each document
and filtering only the html/xml
2nd version without checking the content-type because it's too slow
clean up
forgot 'done()' at the end of the rule
Validation: s/checkbox/select box/ to offer the options 'no validation',
'simple validation' and 'recursive validation'
fix tests
Merge branch 'denis/compound-document' of github.com:w3c/specberus into denis/compound-document

Conflicts:
	lib/l10n.js
	lib/rules/links/compound.js
	lib/rules/validation/html.js