draft about tags that work like docbook 5 example with their differences:

algorithm
  TODO: create translation in two steps
application
assertion
  different roles: claim, corollary, lemma, proposition, theorem, <none>
  title depends on the role:
    claim, corollary, lemma, proposition, theorem, default: assertion
  whether numbering will depend on the role is not decided yet.
definition
example
exercise
  like original docbook tag, but with added type attribute. Possible values are:
  static, gap, <none>.
formalremark
  there exists a docbook tag remark, so our remark is renamed to formalremark
proof

These tags can also have an attribute for, which contains a reference 
identifier.

note that examples and exercises will be handled differently