Use the project object as the source of dependencies instead of 'connecting' to the project

[aloubyansky]

This makes listExtensions, addExtension and removeExtension ~10 times faster.

[maxandersen]

two questions:

1. why removal of tests ?
2. does this knowingly change anything with respect to depednency chains maybe differ or was the connecting part just completely irrelevant to ever do ?

[aloubyansky]

1. Unless there is another kind of CLI (or some other kind of tool) that needs to connect to the project to list, add and remove extensions then the original implementations of those "connector" "BuildFile"s could be kept and the related tests testing those classes directly.
   Otherwise, all of them can be removed.

2. I don't see any reason to connect to the project from the "outside" when we are already "inside" the initialized project.

[ia3andy]

Awesome @aloubyansky this will make the CLI (which call the gradle plugin) way faster!

[maxandersen]

looks good yeah, and based on @aloubyansky explanation that we already are "inside" the project and my limited understanding of the code I'm +1 on this.