[meta] Documentation re-writting

[ArthurSens]

This is an meta issue, grouping all pages that we want to re-write.

Getting Started

• [x] #82
• [x] #83
• Compatibility stays as is.
• [x] #84

Developer Guide

• [ ] #97
• [ ] #96
• [ ] #93
• [ ] #94
• [ ] #95

Platform Guide

• [x] #101 more to come

Community

to be discussed