Update the default Confluence Dashboard welcome message. The new message is here https://extranet.atlassian.com/display/MAR/Dashboard+Welcome+Message

Also, the mechanism for generating the message is poor. Currently we have dashboard-welcome.vm using a small set of property values. We have some HTML in the VM file and some in the property values.

We should probably fix this so that the entire message is in property files, including mark up. Also, we could just make the entire value a default value for the site welcome message instead of needing the dashboard-welcome.vm file.