Create "The Framework Flutter Book"

[ArturAssisComp]

Closes #5

• [ ] Gather all the meaningful information about the framework that is available in the flutter project now
• [ ] Create a prototype for the structure of the book (the summary prototype)
• [ ] Start adding content (start by adding the content gathered from the current flutter project
• [ ] Add a tutorial for implementing tests in the framework
• [ ] Add a "Hello World" tutorial for changing something in the framework