[Implemented] Own context menu for PB IDE editor tab

[uwekel]

Hi,

if you right click on an editors tab, you get the same context menu as in the editors text, but most of the commands are not related to the tab. It would be nice, if we could have a file related context menu with the following entries:

- Save
- Save as...
- Save all
- Reload
- Close
- Close all
- Add file to project
- Remove file from project

Regards
Uwe