Search / filter key maps

[lucabalsanelli]

trafficstars

Developer TODO (don't remove)

• [ ] create new branch. put issue number at start of name
• [ ] update documentation
• [ ] squash and merge
• [ ] delete branch

For example, filter the list of keymaps based e.g. on:

• a character of the trigger
• number of keys involved
• other characteristics like "Override" or "Do not override" default action
• maybe an action
• ...

It goes with #845, #701, #691.

[sds100]

Yeah, that is a good idea