Array parameter setting fails with Int64 parameter type

@jrising David would prefer if you could test out the branch to make sure it solves your problem before we release the new version. The branch you should try is called param-type-v0.9.6, which is slightly different than the branch that the current pull request is on (that one contains other breaking changes that won’t be released until 1.0, but we want to release a 0.9.6 with just this bug fix for you). Whenever you have time, would you mind testing out your code on this new branch? thanks!