Add the PyBash theme for Python developers

[Qiuyi-Hong]

Description

A Colourful and Functional Bash Theme based on Bash-it framework for Python developers. This theme is inspired by atomic theme created by Luis Felipe Sánchez.

Motivation and Context

Many themes available in Bash-it don't support Python virtual environment and the Python version by default. The Atomic theme supports extra configuration to display Python env and version. However, the format and colour display are not consistent and hard to read. To overcome the issues, the PyBash theme is created for general Python developers/data scientists.

How Has This Been Tested?

This theme has been tested on the Ubuntu terminal and the integrated terminal in VSCode. The position of each segment/block has been optimised.

Screenshots (if appropriate):

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• Update colour format
• Use the horizontal line to connect every segment/block
• Show Python environment & version and date

Checklist:

• My code follows the code style of this project.
• If my change requires a change to the documentation, I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.