Keyboard activation of Zoom Mode and Select Mode

[scribbly]

I really love the two "new" modes to Zoom and Select. I use them all the time.

I'd like to have the ability to enable them using keyboard modifier + Mouse for on-the-fly or ad hoc use: for example --

Current Mode is Scroll:

• Shift+Click & Drag: enable On-The-Fly Select Mode
  
• Control + Click & Drag: enable On-The-Fly Zoom Mode
  

Release keyboard - Return to Scroll Mode