Reorganize repo documentation

[bogdanpolak]

1. Move Why use Class Helpers? to separate MD file, merge with The Dark Side of class helpers
2. Move: Good practices, Unit testing and Helpers maintenance to separate Process.MD file
3. Add more helper samples (code snippets) present in the documentation

[bogdanpolak]

Redesign new main page README.md

• Review other OSS project pages (suggestion Golang projects) to choose sections and briefly describe content
  • Installation section: (1) pick a la carte installation / pick-and-use or full repo installation - possible conflicts with existing class helpers
• Choose small and meaningful examples (code snippets)
• Create a compact list for: "Why..", "The Dark Side", "Good practices", TDD / "Unit testing" and "Helpers maintenance"

[bogdanpolak]

Welcome Markdown proposal:
https://drive.google.com/file/d/1xP4URCrTOEv8r805KG97hZIhj2H0mU2e/view?usp=sharing