tokenizer: removed onboguscomment(end)
tokenizer: collect attribute data, use onattribute

attribute data was collected anyway
tokenizer: merge doctype events
tokenizer: split doctype quoted states
tokenizer: decode \0 in tag names, removed onclosetagend
tokenizer: lower case all the things
test: added event tests from htmlparser2
tokenizer: added a simple `debug` option

…which prints the current char and the current state
tokenizer: moved state changes as high as possible

required for updating the state in a handler
tokenizer: added `consumeTYPE` methods
tokenizer: improved entity parsing
parser: support new tokenizer events

still a lot of missing things:
• <style> tag support
• onprocessinginstruction support (also in tokenizer)
…
parser: handle `style` tags, CDATA in HTML
tokenizer: reconsume last char after TAG_OPEN
test: `</ >` is treated as bogus comment
test: got parser tests running