Rename layer-toggle to layer-hold

[oblitzitate]

I've had this discussion before in this thread: kmonad/kmonad#560 (comment)

Basically, the main points are:

• toggle doesn't imply a momentary switch
• toggle's usage in here contradicts its usage in a lot of applications and games
• After not looking at your config for a long time, if you look at it again and try to differentiate between layer-switch and layer-toggle, the average user might be initially confused and have to look for the config reference again.

With kmonad, we eventually settled with adding momentary-layer as an alias, but I still think renaming it layer-hold is the more succinct solution because

• It keeps the layer prefix pattern
• hold is much simpler and more precise for the average user

The author seems to want to reserve hold for patterns like tap-hold, but I believe the average user would easily differentiate between tap-hold and layer-hold because of the different namespaces/contexts.

[jtroo]

I can see why layer-toggle can be a bit misleading. However, a full rename won't happen for some time since that's a breaking change. Similar to kmonad, if added this should be an alias as well.

[jtroo]

Also, if we're going for improving clarity, to me layer-hold is still a bit ambiguous. It's not immediately clear what the difference is between layer-switch and layer-hold since hold could mean the layer is holding... until what? Of course one might guess that -hold doesn't mean the layer, but instead the key, but layer-hold isn't a clear winner.

Though it's longer, to improve this ambiguity I would prefer layer-while-held since for me it improves the ambiguity somewhat; -while-held more strongly suggests that the layer is active while the key is held rather than the layer itself having to do with holding.

[oblitzitate]

Sounds good. I'm fine with layer-while-held as an alias.