regproj.cgi: implement project registration time limit

regproj.cgi: implement project registration time limit

If project registration has not been completed within a set time
limit, specifically $Girocco::Config::project_edit_timeout, display
an error rather than registering the project.

The behavior of an expired registration timeout significantly
resembles a failure of the "Anti-captcha" check, just with a slightly
different message.

With this change, a project registration page that has been sitting
unsubmitted for some time can no longer just be submitted without
an extra step that will require re-entry of the "Anti-captcha" as
well as the project password (twice).

Signed-off-by: Kyle J. McKay <mackyle@gmail.com>