using IRunnableContext for retrieving BuildTargetTreeNode input so progress dialog can be displayed for wizards or in the status bar when on the UI thread (e.g. ManageConfigurationsDialog)
Removes API in BuildTargetTreeNode that presumed all nodes were SBSv1 (didn't appear to be used anywhere)
<contexts>
<context id="hoverHelpContext">
<description>Hover Help Guide</description>
<topic href="resources/help context/dl_hover/html/getting_started.html" label="Overview"/>
<topic href="resources/help context/dl_hover/html/setup.html" label="Set Up"/>
<topic href="resources/help context/dl_hover/html/preferences.html" label="Preferences"/>
</context>
</contexts>