Create naming best practices page

[martinbonnin]

Naming is always the hardest thing but there are some established conventions for naming in the GraphQL community, see:

• https://benjie.dev/graphql/naming
• https://www.apollographql.com/docs/graphos/schema-design/guides/naming-conventions

Other languages also have their own code style/conventions:

• Rust
• Kotlin
• Go

Feels like having official guidance on graphql.org would be a win for the community.