Refactor like_by, follow_by, comment_by => interact_by

#### In order to make InstaPy easier to use we want to cut down on the amount of ways things can be done. One of the ways to start making it simpler is to remove the separate methods `like_by_...`, `comment_by_...` and `follow_by_...` and introducing a common "interface" as `interact_by_...`.

Advantages of this feature:
- Clean up code base
- Less places to fix problems if elements change
- Deduplication of code
- Simpler documentation
- Higher level of abstraction
- Unified interface for users (always `interact_by` followed by e.g. `tags`, `users` etc.) and then controlling interactions by using `set_do_like`, `set_do_comment` and `set_do_follow`

Possible ways of achieving:
- Use the already existing methods as a "base line" on how this can be achieved

> [Back this Issue](https://opencollective.com/instapy)

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###### Feel free to comment with adjustments and improvements