fix title PR merge, include more information

- PR title now includes the PR-number, type (optional)
  and author (username). When no type is given 'merge' is used instead

- Discussion has all trailing white space stripped

- A commit line only contains the first none-breaking line (subject)
  instead of all the details
Merge pull request #200 from sstok/improve-pull-merge

Improve pull:merge with more details