devise install

installed devise and did some basic configurations.  in addition,
updated hard coded admin checks and user_id values to use those values
stored in session variable.
added user link to sidebar
seed error
my account, list users, show users
can_user_check_in? in events_controller
check-in feature and can_user_rsvp added

The code needs to be tested further, but works well in the general
cases.
layout
reports screen and other minor changes
Merge pull request #1 from mnow28/devise

Devise merged