rdbms: Clean up file doc comments

* Document what the LBFactory/LoadBalancer (sub)classes do.

* Move useful descriptions from file doc to class doc so that we don't
  pointlessly maintain it in two places, and to allow for the file
  block to be consistently visually ignored instead of sometimes
  containing useful information.

  This patch removes various non-applicable or unrelated descriptions
  from the file block that were blindly copy-pasted, thus proving my
  point. It also removes two duplicate/clashing definition of the
  'Database' defgroup. Keeping only the primary one in IDatabase.php.

* Move ingroup tag to class block, as indexing the source file
  in Doxygen creates noise in the navigation sidebar and does not
  add add any benefit.

* Fix dead-end reference to a sqlite/README. I'll rework this
  in a later patch.

Change-Id: Iad0e67d766f4a7d5b97e7a471b49f2d8e60c506b

1 files changed, 0 insertions, 2 deletions

diff --git a/includes/libs/rdbms/exception/DBReplicationWaitError.php b/includes/libs/rdbms/exception/DBReplicationWaitError.php
index 9b4bcb3383ed..decf1dae04b5 100644
--- a/includes/libs/rdbms/exception/DBReplicationWaitError.php
+++ b/includes/libs/rdbms/exception/DBReplicationWaitError.php
@@ -16,9 +16,7 @@
  * http://www.gnu.org/copyleft/gpl.html
  *
  * @file
- * @ingroup Database
  */
-
 namespace Wikimedia\Rdbms;
 
 /**