Rename layer-toggle to layer-hold about kanata HOT 3 CLOSED

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.

from kanata.

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.

from kanata.

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

from kanata.