Cannot multiple-select favorites

[BobBooth]

The current UI does not support multiple selection of Favorites. At least for cases where someone is managing a set of favorites (for example, setting up some to export and send as a JSON file to someone, then changing the set of favorites to send to someone else), it would be handy to allow multiple selection in the Favorites pane. From Favorites stress testing.

[saip]

@dfoll Please confirm the features multiple section should honor. Is it only SaveAs(export) and/or delete ?

[dfoll]

@saip for this issue, multiple selection should be honored in two different cases.

Case #1:

Select multiple symbols from the favorites - > click Save As - > only the selected symbols are included in the output .json file

Case #2:

Select multiple symbols from the favorites - > Click Delete - > the selected symbols are removed from the favorites