Remove provider requirements when creating a project

[g3kk0]

Projects at their most basic should be a simple container that environments can be created within.

Currently in order to create a project you need to provide various details about the with regards to the infrastructure provider. This leads to two problems:

• You may not want to expose a global provider across all environments (currently you have no choice)
• Using a project as a simple way to group your environments is more difficult than it should be.

By default the project resource should nothing more than a way to group environments with the option to set default values for the environments within (e.g. provider details if the user wishes).