Ability to rebind the purpose of hard-coded actions.

[MrStevns]

Based on a recent conversation between some of the team members:

One should be able to re-bind the purpose of middle-click and right-click and maybe other bindings as well that can't be used by the standard shortcut logic.

There could exist a few variations of this since we currently also hard-code a few modifiers.

Examples of hard-coded keys or modifiers: Alt: Rotate/Eye dropper Space: Hand tool Right-click: Hand tool

Implementation wise:

• Should be a drop-down menu located on the shortcuts page in preferences.
• Should be able to choose between a limited selection of actions.
  • eg. None, Zoom, Pan, Rotate, Specific Tools, etc ?

[J5lx]

Related: #1016