Remove 2 spaces of indentation to match HTTP/2.0 spec.

It'll make my copy/pastes cleaner in the future.
Merge pull request #16 from willchan/Indentation

Remove 2 spaces of indentation to match HTTP/2.0 spec.
Follow HTTP/2.0 session=>connection terminology change.
Fix ordering in spec of PUSH_PROMISE and SETTINGS frames.
Update html & txt.
Copy HTTP/2.0 error handling section and fix a spelling mistake.
Update html & txt again.
Merge pull request #17 from willchan/Editorial

Editorial changes from HTTP/2.0