Added option in FLAIM to disable direct I/O on Linux and Unix platforms. Re-architected the FTK I/O layer and cleaned up the async interfaces.

git-svn-id: https://svn.code.sf.net/p/flaim/code/trunk@643 0109f412-320b-0410-ab79-c3e0c5ffbbe6

xflaim/src/fdbremov.cpp

@@ -77,6 +77,13 @@ RCODE F_DbSystem::dbRemove(
 		goto Exit;
 	}
 
+	// Close all unused file handles
+	
+	if( gv_XFlmSysData.pFileHdlCache)
+	{
+		gv_XFlmSysData.pFileHdlCache->closeUnusedFiles();
+	}
+	
 	if (pszDataDir && *pszDataDir)
 	{
 		if (RC_BAD( rc = gv_XFlmSysData.pFileSystem->pathReduce(