Inline reaction

[JanVargovsky]

Added InlineReactionReply.

InlineReactionReply is normal UserMessage with a set of reactions and its own callbacks.

example story: user triggers a command bot responds with message e.g. "Do you want 1 or 2?" and adds reactions [1, 2] user clicks on reaction 1 or 2 a callback is fired

[MarkusKgit]

Any chance of getting this updated merged? I think it's quite a useful feature.