Fix deprecation warnings due to Dict syntax change

Fixed dict warnings. Somehow, "Date" to "date" changes are showing up in
my commit even though I think these are from @quinnj? Don't know how
that's even possible from a freshly cloned repo.

If you merge this, I'll leave it to you to bump METADATA.
remove deprecated Dict constructor syntax
Merge pull request #1 from sawcordwell/fixdict

remove deprecated Dict constructor syntax
Julia 0.4 support.