* Modoboa extensions must now declare themselves
* Now using django 1.3 *staticfiles* module
* Better distinction between *static* content and *media* content
see #197
Many updates in this commit:
* first work on the webmail plugin, for now only emails listing and folders browsing is supported...
* New login form,
* New graphical layout (still needing improvments)
* code factoring between webmail and quarantine plugins
* etc.
Antoine Nguyen