Added support for FollowUp line matches

UApp.pas

@@ -173,6 +173,10 @@ begin
       begin
         FLogFileName := AParams;
       end;
+    'followup':
+      begin
+        FCurrentLineFilter.SetFollowUp(AParams);
+      end;
   end;
 end;
 
@@ -253,10 +257,19 @@ var
   lineFilter: TLineFilter;
   groupRanges: TGroupRanges;
 begin
+  if (FCurrentLineFilter <> nil)
+    and (FCurrentLineFilter.FollowUpMatch(ALine, groupRanges)) then
+  begin
+    WriteContent(ALine, FCurrentLineFilter.Filters, groupRanges);
+    Exit;
+  end else
+    FCurrentLineFilter := nil; //We assume, nothing matched.
+
   for lineFilter in FLineFilters do
   begin
     if lineFilter.Matches(ALine, groupRanges) then
     begin
+      FCurrentLineFilter := lineFilter; //Remember the last matching filter
       WriteContent(ALine, lineFilter.Filters, groupRanges);
       Break;
     end;