Add 3D Mobjects - Cone, Cylinder, Line3D, Arrow3D and Torus. (#1026)

* Added new 3D mobjects: mostly taken from dor2727's previous incomplete PR

* Added Torus from 3b1b manim

* Added tests

* Remove personal test file

* Ran black

* Added test for Arrow3D

* Apply suggestions from code review

Co-authored-by: Jason Villanueva <[email protected]>

* Black formatting

* Added documentation, tests failing?

* Added documentation, tests fixed

* Rename self.height to self._height

* Removed unnecessary property.

* Fixed tests

* Apply suggestions from code review

Co-authored-by: friedkeenan <[email protected]>

* Black

* Apply suggestions from code review

Simple changes for now

Co-authored-by: Jason Villanueva <[email protected]>

* Apply suggestions from code review

Possibly breaking changes

Co-authored-by: Jason Villanueva <[email protected]>
Co-authored-by: friedkeenan <[email protected]>

* Update manim/mobject/three_dimensions.py

Fix indentation

Co-authored-by: Jason Villanueva <[email protected]>

* Update manim/mobject/three_dimensions.py

Fix indentation

Co-authored-by: Jason Villanueva <[email protected]>

* Fix things

* Change parameter names for Torus

* Added get_direction method for Cylinder and fixed direction setting

* retrigger checks

* Update manim/mobject/three_dimensions.py

remove dead comment

Co-authored-by: Jason Villanueva <[email protected]>
Co-authored-by: friedkeenan <[email protected]>

Author: 3 people