modules: Add Role Handbooks module with seven new pages
    
    This commit creates a new module with placeholder pages for each of the
    seven roles specified in the Nest 2021 hackfest wiki planning doc:
    
    * Ambassador Emeritus
    * Ambassador Mentor
    * Amabassador
    * CommOps team member
    * Join SIG team member
    * Marketing Team member
    * Reps to Mindshare Committee
    
    Signed-off-by: Justin W. Flory (he/him) [Fedora Project] <jwf@fedoraproject.org>