Add intention action for replacing method calls to get() with bracket syntax

Task 0 for #kotlin-students:

Kotlin allows the array access operator (e.g. list[0]) to be overloaded:
the bracket syntax is mostly equivalent to calling the get() method.
Add an intention action for transforming get() calls into the bracket
syntax where possible:

- The call must have an explicit receiver (dot expression).
- There aren't any arguments passed by name.
- There is at least one argument.