Enhancement: Quick file open via sidebar documents tab

[blacksqr]

It would be extremely helpful for me in navigating my large project if I could use the directories visible in the sidebar documents tab to bring up the file open dialog showing the files in a specified directory.

That is, I'd like to be able to right-click on a directory node in the sidebar documents tab and see an "Open File..." option. When I select that option, the file selection dialog comes up already showing the contents of the directory I right-clicked on. That way, I can immediately select a file and open it, rather than opening the file selection dialog in the usual way and having to navigate manually through my directory hierarchy to find the file I want to open.

[elextr]

Two workarounds:

1. the open dialog opens in the directory of the current file, so select a file already open in the relevant directory before open, but the documents pane only shows directories of files that are open, so:
2. use file browser plugin which shows all files and directories

Otherwise pull requests are welcome.