Allow project admins to choose notification and permission scheme from fixed list.

Rather than always bugging a jira-administrator to adjust notifications/permissions, the jira-administrator could create a few sanctioned/official schemes that the Administer Projects (Project Role Administrators by default) could select from.

notificationscheme and permissionscheme need a new DB column to the effect of 'ALLOWPROJECTADJUST' or 'SANCTIONEDLIST' default NULL = 0/FALSE/NO

Thus any with NULL are not presented in a drop down list.

(Will have to expose the button for actions > 'use a different scheme' to the Administer Projects permission).

JRA-28184 is marked as a bug in documentation, so hence this new feature request.