memoutil: use 2 spaces instead of TAB for indentation

TAB width is too wide for qt.

Author: quark-zju

frontend/memoutil.pas

@@ -127,7 +127,7 @@ function Indent(S: string): string;
   if S.IsEmpty or S.Trim.IsEmpty then begin
     Result := S;
   end else begin
-    Result := #9 + S;
+    Result := '  ' + S;
   end;
 end;
 
@@ -259,8 +259,8 @@ procedure SmartKeyDown(Memo: TMemo; var Key: word; Shift: TShiftState);
       end;
     end else begin
       if Memo.SelLength = 0 then begin
-        // No selection. Insert a TAB.
-        // Memo.SelText := #9; Key := 0;
+        // No selection. Insert 2 spaces.
+        Memo.SelText := '  '; Key := 0;
       end else begin
         // With selection. Indent lines.
         Sel := GetMemoSelectedLines(Memo);