i177: Restructure project - move widget files into folders

[nickmeinhold]

Fixes #177

• created folders under widgets folder and moved existing files into relevant folders
• that is literally the only changes in this commit

There is still a fair bit of restructuring to do imo but I thought it would be easier all round if we do it in small steps.

The goal here (as I see it) is just to make everything easier to find, I'm more than happy to discuss a different structure. Thanks!