[RCP] location URI

location URI 定義如下

Table 1.

Contribution to	Description	Uri
Application menu	應用程式的menu區	"menu:org.eclipse.ui.main.menu"
Application toolbar	應用程式程式的toolbar區	"toolbar:org.eclipse.ui.main.toolbar"
View toolbar	在view的toolBar區	"toolbar:viewId". For example to display a menu to view with the Id "View1" use "toolbar:View1".
Content menu / pop-up	Command is displayed in a content menu, e.g. right mouse click on an object	n.a.