PR suggestion: Implement height & width resize (but not smart resize) for floating windows

[Stefan-Heimersheim]

I saw discussion in issue #9 about resizing floating windows. The main point of contention seems to be how to handle smart resize.

I'm thinking of implementing just heigh and width resizing, and leaving smart resizing to be implemented later. So that the PR wouldn't be blocked by resolving those discissions.

The contributors guide suggested I ask here before I start working on a PR, so I haven't looked at implementing this yet. Let me know if this sounds like a good idea!