Mouse input via touch

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Is your feature request related to a problem? Please describe.
As a user I want to use the emulator on the go without a hardware mouse. So I want to use touch movements on my screen for cursor movements in workbench etc.

Describe the solution you'd like

Expected behavior

1. Cursor moves relative to touch input
2. Left mouse button can be pressed by single press
3. Right mouse button can be pressed by single press with two fingers

Describe alternatives you've considered

1. Right and middle mouse button could be emulated via buttons in onscreen controller (maybe hidden in "meta menu")