Forex sessions with daylight savings

This will adjust with Daylight Savings (DS) however you will need to update the start and end dates of DS once each year. That said, it's valid for 2021 and I'll try to remember to update this script each year so people don't have up to do the update of the DL start and end dates.

If there is a way to know these dates automatically in pine script someone please let me know.

Notice that Sydney has an offset of -1 instead of 1 for DS since being on the other side of the planet (sorry flat Earthers but this is a side-effect of a globe) they need to put their clocks backwards for DS instead of forwards.

Features:

• Shows sessions for: Frankfurt, London, New York, Sydney & Tokyo
  
• Includes Daylight savings changes
  
• Has a legend you can display and hide to see which colors are for which sessions around the world
  
• Allows you to show or hide each session individually
  
• Allows you to display the legend in the same opacity as the indicators or 0 opacity to make it more readable.
  

This is my first public script so feedback most welcomed.