Mpl-plotter

Demo pads: custom bounds bug corrected.

Cleaned dependencies and improved code documentation.

Comparison function: restored control over automatic curve color assignment.

- Heatmaps: axis bounds bug corrected, input restricted to NumPy arrays
- Code quality improvements

General:
- Improved control over tick number.

Comparison:
- Added support for multiple x arrays

Panes
- Added support for multiple x arrays and lists of arrays
- Added figure as input
- Added control over plt.subplots_adjust axis positioning parameters (top, bottom, left, right, wspace, hspace)

Scatter plots:
- Marker class: retrieve all available Matplotlib scatter markers by index (sorted by personal preference), solid or hollow

Comparison function: added control over automatic curve color assignment.