Package release for the C Raylib 4.2 Post-Release 1

This release was made as output of another project, as mentioned in #45.

Features:

PEP8 naming convention;
Type hinting (instead of type annotation);
Structures with functions as methods and properties (like some_vec2.length or some_sound.play();
Vector{2,3,4}, Rectangle and Color have attribute swizzling (like my_vec4 = some_vec2.xxyy);
Pretty printing: most structures implement __str__() and __repr__() in a friendly way;
Context managers: begin_* and end_* functions can be called as context managers;
Context managers for some structures: Camera{2,3}D, Shader and others;
RLGL and RayMath functions exposed

Colors passed as sequences in functions had the red component repeated in the green one;
Texture structure wrapped without functions as methods;
Rectangle missing __str__ and __repr__ default implementations;
Context managers not being included in __all__;

Vector{2,3} overload for binary operators +, -, * and / (// not implemented); unary +, -, and abs():
Operators are supported between:
- Vectors;
- Vectors and ints or floats;
- Vectors and sequences of ints or 'float's,
- Vectors and Matrixes, for multiplication only.
Better swizzling for Rectangle:
When doing swizzling in rects, more attributes become available:
- c, m as center and middle: x + width * .5 and y + height * .5 respectively;
- r, b as right and bottom: x + width and y + height respectively;
- swizzling can include from 1 up to 4 attributes, not only 4 anymore.

Please, take a look at this project: raylibpyctbg