Problem: missing documentation for analysts (manager)

[zolotokrylin]

Existing events PR_APPROVED and PR_REJECTED were updated to comply with our needs, meaning the sender is the owner of the PR and these events should be considered as approve or reject received by that user.
The newest events PR_REVIEW_{APPROVE|REJECT|COMMENT} are for reviewers purpose (the sender gave a review).

Originally posted by @georgeciubotaru in #248 (comment)

This needs to be documented in the README.
We will forget this soon (I will for sure because it is not very intuitive).

[zolotokrylin]

Problem: the link to analysts (manager) interface is missing