Pyconics

- The `CConic.pole()`, `CConic.polar()`, `CConic.area()`, and
`CConic.sequence()` methods have been implemented in `CConic` class.
- The global variable `origin` has been renamed to `corigin`.
- The global variable `tol` has been renamed to `ctol`.
- The global variable `const` has been renamed to `cconst`.
- The file `README.md` has been updated to show examples of how to
work with conics.
- `plot()` method in `CAxes` class can now show conics on screen.
- `CConic` class has been incorporated into `pyConics`.
- `coef_angular()` and `coef_linear()` methods in `CLine` have been
created.

- import `numpy` as np was added to the example
'Creating an empty figure and its four axes' in `README.md`.
- A warning was inserted in `README.md` to advise you how to
install `pyConics` on Linux OS without a GUI, such as Ubuntu
on WSL2.

- The `dot()` function in `utils.py` had a bug that was fixed.
- The pictures in `README.md` had unresolved links. This bug
was fixed.

- `pyConics` classes have been renamed by adding a prefix `C` in
front of every class name, i.e., `Point` class has become `CPoint`
and `Line` class has become `CLine`.
- `CFigure` and `CAxes` classes have been created. Thus, they can
be used to plot `CPoint`, `CLine`, and in the future `CConic`.
- A bug was fixed in `utils.dot()` method.
- `function.py` has been renamed to `utils.py`.
- requirement: `python` version was downgraded to 2.10.
- requirement: `numpy` version was downgraded to 1.25.

- A dependency conflict has been resolved.

- A bug has been fixed in `README.md`.