Add creator id, fullname, email; creators emails and contrib emails

- Add dublin-core substitutions: creator, creator_fullname, creator_email,
  creators_emails and contributors_emails
Test creator id, email, fullname, creators emails and contrib emails
Merge pull request #6 from eea/1.0.x

Add creator id, fullname, email; creators emails and contrib emails (git cherry-pick from master branch)