Add support for autocomplete

[valentin-p]

Steps to Reproduce

1. Create a new setup for a mocked class.
2. Tap Cltr+Space inside the parenthesis the method.
3. The autocomplete should offer one line per overload of that method.

Expected Behavior

See this archived repository:
https://github.com/Litee/moq.autocomplete

See the readme of the project above.

Actual Behavior

No autocomplete currently