Merge with dev

[onsdagens]

Master has fallen quite a bit behind.

This merge contains, among other things

• A model of Hippomenes, a rv32i core extended with the N-CLIC interrupt controller allowing zero-latency interrupt dispatch and return.
• Revamped, egui based GUI
• WiP graphical model editor
• Egui view for all of the RISC-V components
• Data memory view, Instruction memory view, Register file view panes for the egui based GUI
• The RISC-V model now has a graphical view that makes (at least some) sense
• Massive performance improvements to the egui view
• Improvements to documentation
• Smaller fixes and features that i've forgotten about

[onsdagens]

I will get back to this tomorrow, but it is time!

[onsdagens]

Vizia has seen some changes since we last looked into it, leaving the Vizia-based GUI broken.

Two options exist:

• Point to some old commit
• Refactor based on current Vizia

I figure the Vizia GUI has fallen enough behind the egui version that there is no point keeping it alive. Instead, i've refactored it to build under the most recent version, with no guarantees to correctness. If someone in the future is willing to work on making it feature-complete (general GUI exploration under different frameworks sounds like a nice master's thesis for someone not that interested in the regular embedded stuff, but still into Rust), that's fine, for now we keep it around as legacy.

[onsdagens]

Also, this includes #40

[onsdagens]

Addresses #60 #52 , (the egui )half of #17 , #9