Added the users pending interface.
Modified the registration form. (Checks, username field, etc)
Changes before completely redoing this again.
Full functionality.
Cahnged the XWikiPreferences file.
Cahnged the XWikiUsers.
The registration form is PhenomeCentral.RegistrationWiki.
There are files from previous commits that should be not pulled.
Small fixes.
Changed the email (on request) message body.
Merge branch 'pending-users' of github.com:antonkatz/phenomecentral.org into antonkatz-pending-users
[misc] Update override document