Update server service help.
Improve filter type explanation in scc merge section

- Expose both forms of inclusion/exclusion by PR number
- Expose inclusion/exclusion of submodule PRs by number
Add section about scc travis-merge command

- Expose the comment parsing strategy to define the include filters
Pluralize filters as suggested by Mark
Replace Pull Request by its abbreviation
Merge pull request #479 from bpindelski/rebased/develop/winservice

Update Windows service docs (see #11448) (rebased onto develop)
Merge pull request #481 from sbesson/rebased/develop/travis-merge

Travis merge documentation (rebased onto develop)