According to the official documentation
> Like other classes in D3, layouts follow the method chaining pattern where setter methods return the layout itself, allowing multiple setters to be invoked in a concise statement.
And d3.layout.treemap.sticky specifically https://github.com/d3/d3-3.x-api-reference/blob/master/Treemap-Layout.md#sticky should return Treemap<T>.
This file should comply with the actual API, why it is not?
Submiting this MR to your consideration
BREAKING CHANGE:
* feat(d3) :add d3-contour, d3-fetch, and d3-scale-chromatic
* refactor(d3): remove d3-request and d3-queue in favour of d3-fetch
* chore(d3): update major version number to 5.0
* chore(d3): move legacy 4.x definitions with old dependencies into `v4` folder. Apply path-mapping to d3-scale v1 and d3 v4. Update minor version number to 4.13
Added optionality to parameter in insert
Added number as initial value in Link
Added Date as allowed return für brushing on Date charts
Extended Primitive
* Minor Version updates:
* [d3-drag] Added `touchable(...)` support
* [d3-drag] Bumped minor version to 1.2
* [d3-zoom] Added `touchable(...)` support
* [d3-zoom] Bumped minor version to 1.6
* d3
* Bump minor version to 4.11
* [d3-zoom] Update to 1.5
* [Feature] Add `translateTo(...)`
* [Doc] Update some JSDoc comments
* [Chore] Bump minor version number
* [d3-zoom] Bump Minor Version number.
* [d3-shape]
* [Fix] Change `pointRadius` to `pointRadial`
* [d3-shape] Fix test for pointRadial
* [d3-axis]
* [Doc] Update some comments.
* [d3-time] [Doc] Some JSDoc updates.
* [d3] [Chore] Bump minor version to 4.10
* Update d3-format to v1.2
* [Feature] Adds support for optional "percent" suffix in locale definition.
* Added tslint.json file
* [d3-array] Update to version 1.2
* [Feature]: Add `tickIncrement(...)`
* [Fix]: Fix incorrect return type of tickStep(...). The correct return type is `number` instead of `number[]`
* [Chore]: Updated related comments
* [d3] Update minor version to 4.8
* Fix d3-format related linting errors.
