Capture Adopt LiveView Notes 📝

[nelsonic]

@MikeRund having followed the Adopt LiveView course
and made loads of notes in your (paper) notebook. 📝
Please:

• Decide (comment) if this repo is the most appropriate place for notes
  or if we should put them in dwyl/learn-phoenix (which needs a reboot ♻️)
• Create a new page in this repo e.g: adopt-liveview-notes.md
• Capture as much of your notes as possible.

Related to: #223

[MikeRund]

I'll get the notes summarised and typed up on local readme and then assess which location would be best for them.
It is a beginner introductory course but I definitely think there's loads of value for a new phoenix developer!

[MikeRund]

Pull request created! ( See #228 ).
I opted to contain the notes in this project, adding a lengthy file to the learn-phoenix seemed wrong for an introduction to the tech.
This way, for someone reviewing the counter-tutorial they have the option to dig a little into LiveView if they desire.