Change "created by" to "maintained by" in repo info
    
    This changes the string in the repo info page that
    displays the main admin of a repo from 'created by' to
    'maintained by'. This change is due to the fact that ownership
    of a repo can be changed, and the current main admin my not
    be the user that actually created the project.
    
    Also adds a second line that shows the creation date of a
    repo. Also changes the owner string in userdash projects
    to maintainer, and the main admin in the repo acls list
    on repoinfo to maintainer.
    
    Fixes #4055