Add new detail panel widget to Maven.
Changed name of plugin directory
Rename plugin

org.csstudio.dls.detailpanel -> org.csstudio.opibuilder.widgets.detailpanel

Changed:
* Package of source files
* Extension points to point to new package names
* Removed all DLS references
* Name in pom.xml and MANIFEST.MF
* Name in DLS product feature