Put all directories and images in database, use the info to associate an image to each artist

src/libs/database/test/CMakeLists.txt

@@ -4,6 +4,7 @@ add_executable(test-database
 	Cluster.cpp
 	Common.cpp
 	DatabaseTest.cpp
+	Directory.cpp
 	Image.cpp
 	Listen.cpp
 	Migration.cpp