[cowebx] Sample Admin UI and SessionManager API for Java Server about coweb

[vinomaster]

Target home this code is: cowebx-adminui

[vinomaster]

We have decided that the IBM PBS effort will contribute this initial sample.

[vinomaster]

Here now is an attempt to expand on this issue.

When developing hosted OpenCoweb solutions to support multiple meetings may occur at the same time using the same coweb-app, we need the notion of a SessionManager as well as a UI that will all for (a) creation of a new meetings (b) joining new meetings.

The notion of a session can be described as a unique cowebkey. Each meeting URL for a given application is provided a unique CowebKey so that multiple instances of a given meeting can occur at the same time. Unique URL yields unique session.

We have had a discussion several times about how to implement this issue:
[a] SesssionManager API gets added to coweb repo and becomes an extension to our framework
[b] SesssionManager API gets added to coweb repo and a sample UI gets added to cowebx repo
[c] A sample SessionManager API and UI are added to cowebx repo

We have decided that [c] is the desired approach. SessionManager API will be an implementation of the base coweb extension API.

[vinomaster]

This issue pertains to predefined meetings (sessions) and not the functionality that was dropped in M6 w(0.6) whereby named sessions are now supported as well as an API callback for what sessions are currently running.

See issue #39 for more related details.

[vinomaster]

Closing Issue as a duplicate of #49