I just did an install of NodeBB 0.8.2 and it installed nodebb-plugin-emailer-mandrill 0.3.1 with it which is only compatible with NodeBB 0.9.^. In addition to the declared version problem I was also getting a socket.io/helpers related error on NodeBB startup until I removed the mandrill plugin.
I worked around this problem by removing mandrill and then installing it like this:
@exodo composer #5 is a bad PR, as I pointed out in the PR itself. I know what you mean though, it's annoying waiting weeks for PRs to be merged. However, it also takes time to test PRs before merging.