Move 'snippet' queries to 'snippets' folders

cpp/ql/examples/snippets/emptyblock.ql

@@ -0,0 +1,13 @@
+/**
+ * @name Empty blocks
+ * @description Finds empty block statements
+ * @tags empty
+ *       block
+ *       statement
+ */
+
+import cpp
+
+from Block blk
+where blk.getNumStmt() = 0
+select blk