XAMEETINGS-52 : Adjust the single meeting view UI

XAMEETINGS-52 : Adjust the single meeting view UI
and affects and solves as well:
XAMEETINGS-53 : Adjust the single meeting edit UI

To review details: 
http://jira.xwiki.org/browse/XAMEETINGS-52 and http://jira.xwiki.org/browse/XAMEETINGS-53
and perhaps: http://design.xwiki.org/xwiki/bin/view/Proposal/MeetingApplicationDesignII

There is a portion of the UI missing, because it lacks the functionality behind: http://jira.xwiki.org/browse/XAMEETINGS-54 but this does not have a significant impact on the solution provided, the rest of the UI is functional.