Ticket #269: Add missing JavaDoc for MySQLConnection, remove whitespace at ends of lines.

extensions/guacamole-auth-mysql/src/main/java/net/sourceforge/guacamole/net/auth/mysql/MySQLConnection.java

@@ -68,9 +68,15 @@ public class MySQLConnection extends AbstractConnection {
      */
     private List<ConnectionRecord> history = new ArrayList<ConnectionRecord>();
 
+    /**
+     * Service for creating and retrieving objects.
+     */
     @Inject
     private ProviderService providerService;
 
+    /**
+     * Set of all currently active connections.
+     */
     @Inject
     private ActiveConnectionSet activeConnectionSet;