text: Title: Rename `Client` to `Prisma`
  Body: ## Problem
  
  <!-- A clear and concise description of what the problem is. Ex. I'm always frustrated when [...] -->
  
  When using Prisma alongside other frameworks, it is not immediately clear what `Client` is a reference to - is it a HTTP Client? An external API Client?
  
  ## Suggested solution
  
  <!-- A clear and concise description of what you want to happen. -->
  
  We should rename the `Client` to `Prisma`, this makes it very clear. However we should also keep the `Client` name for backwards compatibility.
  
  ```py
  class Prisma:
      ...
  
  Client = Prisma
  ```
  
  We should also update the documentation accordingly.
  
  ## Additional context
  
  There is one downside to this, the python convention is to instantiate classes with the lowercase class name, e.g.
  
  ```py
  prisma = Prisma()
  ```
  
  As the package is also named `prisma` there could be name conflicts that arise from this.
  