[Tasklist] HmGui refactoring and extending

[HaronK]

- [ ] https://github.com/Limit-Theory-Redux/ltheory/issues/160
- [ ] https://github.com/Limit-Theory-Redux/ltheory/issues/166
- [ ] https://github.com/Limit-Theory-Redux/ltheory/issues/195
- [ ] #211
- [ ] https://github.com/Limit-Theory-Redux/ltheory/issues/194
- [ ] https://github.com/Limit-Theory-Redux/ltheory/issues/257
- [ ] https://github.com/Limit-Theory-Redux/ltheory/issues/164
- [ ] [HmGui] Get rid of explicit Input parameter in some HmGui methods
- [ ] [HmGui] Get rid of widgets hierarchy in UIRenederer
- [ ] [HmGui] Element focus (tab focus)