C++ / JS / python: Be consistent in TRAP sections

This makes the
    /*- Database metadata -*/
and
    /*- Overlay support -*/
sections consistent between the languages.

Author: igfoo

cpp/ql/lib/semmlecode.cpp.dbscheme

@@ -2379,6 +2379,8 @@ link_parent(
     int link_target : @link_target ref
 );
 
+/*- Database metadata -*/
+
 /**
  * The CLI will automatically emit applicable tuples for this table,
  * such as `databaseMetadata("isOverlay", "true")` when building an
@@ -2389,6 +2391,8 @@ databaseMetadata(
   string value: string ref
 );
 
+/*- Overlay support -*/
+
 /**
  * The CLI will automatically emit tuples for each new/modified/deleted file
  * when building an overlay database.

javascript/ql/lib/semmlecode.javascript.dbscheme

@@ -1195,11 +1195,23 @@ configLocations(
 @configLocatable = @config | @configName | @configValue;
 
 /*- Database metadata -*/
+
+/**
+ * The CLI will automatically emit applicable tuples for this table,
+ * such as `databaseMetadata("isOverlay", "true")` when building an
+ * overlay database.
+ */
 databaseMetadata(
   string metadataKey: string ref,
   string value: string ref
 );
 
+/*- Overlay support -*/
+
+/**
+ * The CLI will automatically emit tuples for each new/modified/deleted file
+ * when building an overlay database.
+ */
 overlayChangedFiles(
   string path: string ref
 );

python/ql/lib/semmlecode.python.dbscheme

@@ -47,18 +47,24 @@ externalData(
   string value : string ref
 );
 
-/*- Overlay support -*/
+/*- Database metadata -*/
 
 /**
- * The CLI will automatically emit the tuple `databaseMetadata("isOverlay", "true")`,
- * along with an `overlayChangedFiles` tuple for each new/modified/deleted file,
- * when building an overlay database, and these can be used by the discard predicates.
+ * The CLI will automatically emit applicable tuples for this table,
+ * such as `databaseMetadata("isOverlay", "true")` when building an
+ * overlay database.
  */
 databaseMetadata(
   string metadataKey : string ref,
   string value : string ref
 );
 
+/*- Overlay support -*/
+
+/**
+ * The CLI will automatically emit tuples for each new/modified/deleted file
+ * when building an overlay database.
+ */
 overlayChangedFiles(
   string path : string ref
 );