[db] Update v19.05 to v19.06

- queue table: define id column as AUTOINCREMENT (requires drop+create)
- queue table: add column queue_version
- files table: update http-stream virtual paths (constructing the
virtual path for http-streams changed in pr #449, this migrates existing
databases to be consistent to the newly created paths)

src/db_init.h

@@ -26,7 +26,7 @@
  * is a major upgrade. In other words minor version upgrades permit downgrading
  * forked-daapd after the database was upgraded. */
 #define SCHEMA_VERSION_MAJOR 19
-#define SCHEMA_VERSION_MINOR 05
+#define SCHEMA_VERSION_MINOR 06
 
 int
 db_init_indices(sqlite3 *hdl);