V2.0

- update css to be more compatible with nested contentpanels

- compatible with I18NLayer

- submit to Plone as a portlet proposal

- Local published event/Local published news viewlet

- modify portlet permissions, only manager role can see portlets

- Also, you mention in the documentation that there are heirarchical content
  panels - I assumed that when you click the 'add panel' button inside a panel
you can do that, but actually it just adds the panel after the one you click.
How do you put panels inside other panels?

UI should be refined, how about this way:
1. in the popup add panel window, user can select to add a new
sub-contentpanels
2. after that, the sub-contentpanels is auto-created in the same folder and
added on the panel with the correct viewlet.

It should be easier to use and the code is still very simple. 
