WIP v2.1.0

Hiatus is up! Time to work on `v2.1.0`. Any help is welcome.

Here's a list of features and fixes that will be included in `v2.1.0`:
- [ ] Implement navigation drawer
- [ ] Implement scrollable tabs
- [ ] Implement `<textarea>` form element. Its style should look like the `<input>` element but grows vertically when text is long.
- [ ] Fix switches (Issue #86)
- [ ] Fix radio buttons
- [ ] Fix checkboxes (Issues #85, #86)
- [ ] Fix keyboard overlapping fields of a form