Exposing event request in interaction handler

[Vladmel1234]

Hey i in order to present error messages in View in need to preform Ack to the raw event with Error payload https://api.slack.com/surfaces/modals#displaying_errors
In order to do it properly i need request inside interaction handler
this issue will be follow by PR

there is open PR #19 that doing this but it looks like it wont be merged soon because of fix requests i am opening one with requests fulfilled in case you prefer to merge original one i am more than fine with it but it looks like its in stale state