* `TeXUtils`
* added `matrix` function
* `TeXBase`
* made `to_latex` standard string method, which `__str__` now points to
* `LaTeX`
* added `LaTeXResource` subclass of `TeXResource` for clarity
* `LaTeXDocument`
* removed 'amsmath' from default packages
* added saving using bytes and `encoding` option
* fixed saving bug
* `LaTeXEnvironment`
* `TikZBase`
* reworked major systems
* added `to_tikz` (inspired by the `to_latex` change), `__hash__`, and `__eq__` as abstract methods in `TikZBase.TikZWriteable`
* added final implementations of `to_tikz`, `__hash__`, and `__eq__` to `TikZNamed`
* renamed `TikZDefinesNamed` to `TikZDefinesWriteable`
* implemented more sophisticated registering as part of `TikZDefinesWriteable`
* added `TikZArrowDirection` enum
* added `TikZArrowDirection` as argument of the `_TikZArrow` enum values
* made `TikZStyle` inherit from `TikZDefinesWriteable[TikZColor]`
* improved Style concat, and `__len__` methods of `TikZStyle`
* added `EMPTY_STYLE` constant
* implemented new handling of objects in `TikZPicture`
* `TikZ`
* added implementations for `to_tikz`, `__hash__`, and `__eq__` to `TikZWritebale subclasses`
* fixed bug of polar coordinate calculation in `Point`
* fixed `radius` bug in `PolarPoint`
* added `raw_coordinate` property in `TikZNode`
* added staticmethod `find_node_relations`, and now automatically calculate node relations in `TikZPath`
* changed handling of coordinates in `TikZPath`
* implemented a lot more functionality of `TikZGraph`
* added `demo2` in `_test.demo`
* added `test_TikZBase` in `_test` (**BUT CURRENTLY OUTDATED AND BROKEN**)