* Only use -no-pdf for xelatex rendering
* Instead of tracking du and dv points on surface, track points off the surface in the normal direction
This means that surface shading will not necessarily work well for arbitrary transformations of the surface. But the existing solution was flimsy anyway, and caused annoying issues with singularity points.
* Have density of anchor points on arcs depend on arc length
* Allow for specifying true normals and orientation of Sphere
* Change miter threshold on stroke shader
* Add get_start_and_end to DashedLine
* Add min_total_width option to DecimalNumber
* Have BackgroundRectangle.set_style absorb (and ignore) added configuration
Note, this feels suboptimal
* Add LineBrace
* Update font_size adjustment in Tex
* Comment tweak
* Directly print traceback
Since the shell.showtraceback is giving some issues
* Make InteracrtiveSceneEmbed into a class
This way it can keep track of it's internal shell; use of get_ipython has a finicky relationship with reloading.
* Move remaining checkpoint_paste logic into scene_embed.py
This involved making a few context managers for Scene: temp_record, temp_skip, temp_progress_bar, which seem useful in and of themselves.
* Change null key to be the empty string
* Ensure temporary svg paths for Text are deleted
* Remove unused dict_ops.py functions
* Remove break_into_partial_movies from file_writer configuration
* Rewrite guarantee_existence using Path
* Clean up SceneFileWriter
It had a number of vestigial functions no longer used, and some setup that could be made more organized.
* Remove --save_pngs CLI arg (which did nothing)
* Add --subdivide CLI arg
* Remove add_extension_if_not_present
* Remove get_sorted_integer_files
* Have find_file return Path
* Minor clean up
* Clean up num_tex_symbols
* Fix find_file
* Minor cleanup for extract_scene.py
* Add preview_frame_while_skipping option to scene config
* Use shell.showtraceback function
* Move keybindings to config, instead of in-place constants
* Replace DEGREES -> DEG
