Add an easy way to reload an .rrd from disk

[facontidavide]

Describe the annoyance
In my application I DO NOt want to do streaming but i prefer to save data in a file and load it wiht Rerun.

The problem is that reloading a file is very cumbersome, in my opinion.

When loading a file I want to:

1. Have a "Open Recent" list in the menu above
2. Rerun should remember the folder of the last file opened and use that as default folder
   3, We have a "reload" button where the arrow is (image below) to reload data from the previously loaded file.