Graphs improvements

- Show begin and end time in the graph info table
- Show "Custom" zoom resolution when zoom is active and make it clickable to jump to it later
- Hide past time comparison series by default if too high

scripts/lua/get_ts.lua

@@ -34,6 +34,7 @@ end
 
 local options = {
   max_num_points = tonumber(_GET["limit"]),
+  initial_point = toboolean(_GET["initial_point"]),
 }
 
 -- convert the query into fields