Added print methods as optional standard
Added support for MPL 2
Fixed spec states
Added note to RFC 22
Added list of known implementations
Some updates to C4.1

- apologies for modifying a stable text, these changes are backwards
  compatible and document what has become standard practice

- no need to create separate issues for spontaneous pull requests.

- tolerance of merging own pull requests in exceptional situations.
Merge pull request #36 from hintjens/master

Updates to C4.1