added qse_awk_rtx_pushrcb() and qse_awk_rtx_poprcb().

deleted qse_awk_rtx_setrcb() and qse_awk_rtx_getrcb().
added 'close' to qse_awk_rcb_t
added builtin functions 'setenc' and 'unsetenc' to awk/std.c
added qse_getcmgrbyname()
added builtin functions 'setenc' and 'unsetenc' to awk/StdAwk.cpp

qse/lib/awk/parse.c

@@ -4832,7 +4832,7 @@ static qse_awk_nde_t* parse_primary_ident (
 
 	/* check if namedup is an intrinsic function name */
 	fnc = qse_awk_getfnc (awk, namedup, namelen);
-	if (fnc != QSE_NULL)
+	if (fnc)
 	{
 		if (MATCH(awk,TOK_LPAREN))
 		{