Keyboard shortcut

I think we should add keyboard shortcuts for every menu item to speed up the workflow for the users.

An idea could be for example:

File

Menu entry	Shortcut
Clear files	Ctrl+R
Load session	Ctrl+L
Save session	Ctrl+S
Clear session	Ctrl+C

Export

Menu entry	Shortcut
Export diffractograms	ALT+F
Export fit result table	ALT+T
Export diagram	ALT+D
Export pole diagram	ALT+P

Image

Menu entry	Shortcut
Mirror	Ctrl+Shift+M
Global intensity scale	Ctrl+Shift+G
Link the four cut settings	Ctrl+Shift+L
Show crosshair	Alt+C
Show bins	Alt+B

Diffractogram

Menu entry	Shortcut
Show fitted background	Alt+F
Remove baseline ranges	Ctrl+Shift+B
Clear baseline ranges	Alt+B
Remove peak	Ctrl+Shift+P
Clear peak	Alt+P
All measurements	Ctrl+A
Fixed intensity scale	Ctrl+I

View

Menu entry	Shortcut
Spawn table	Alt+T
Spawn diagram	Alt+D
Spawn pole figure	Alt+P
Reset	Alt+R

Help

Menu entry	Shortcut
About	F1
Opens docs in browser	F2
Open steca releases page	F3