Fix SqliteDatabase to start the thread

modules/ripple_app/data/ripple_SqliteDatabase.cpp

@@ -41,6 +41,8 @@ SqliteDatabase::SqliteDatabase (const char* host)
     , mWalQ (NULL)
     , walRunning (false)
 {
+    m_thread.start ();
+
     mConnection     = NULL;
     mAuxConnection  = NULL;
     mCurrentStmt    = NULL;

modules/ripple_app/data/ripple_SqliteDatabase.h

@@ -7,7 +7,9 @@
 #ifndef RIPPLE_SQLITEDATABASE_RIPPLEHEADER
 #define RIPPLE_SQLITEDATABASE_RIPPLEHEADER
 
-class SqliteDatabase : public Database
+class SqliteDatabase
+    : public Database
+    , LeakChecked <SqliteDatabase>
 {
 public:
     explicit SqliteDatabase (char const* host);