Assembly and Namespace change

[rafsanulhasan]

I would like to request you to rename the project to "ArangiDB" excluding the "NetStandard" because:

1. In .NET ecosystem, we don't usually append framework names in the main implementation of ANY Library
2. Exceptions: We append Framework's name only for platform specific implementations
   Examples: SwashBuckle provides APIs for Swagger Tools, SwashBuckle.AspNetCore provides DI services for AspNetCore
3. We can create a separate project "ArangoDB.AspNetCore" to provide DI services
4. The main Arango library remains only "ArangoDB" that is built on NetStandard.