Model: Add Clear() method to empty out existing depot info.

src/apps/haiku-depot/Model.cpp

@@ -287,6 +287,13 @@ Model::AddDepot(const DepotInfo& depot)
 }
 
 
+void
+Model::Clear()
+{
+	fDepots.Clear();
+}
+
+
 void
 Model::SetPackageState(const PackageInfoRef& package, PackageState state)
 {

src/apps/haiku-depot/Model.h

@@ -35,6 +35,8 @@ public:
 			const DepotList&	Depots() const
 									{ return fDepots; }
 
+			void				Clear();
+
 			// Access to global categories
 			const CategoryRef&	CategoryAudio() const
 									{ return fCategoryAudio; }