ComicsAlliance has published this helpful future timeline of all superhero movies that will come out till 2020. It's a list of all the confirmed ones—its missing "one or two movies from Marvel" in 2019, apparently—and of course dates may change, but this is pretty much all of it.
Our timeline makes the assumption that the Warner Bros movies will be released in the order listed in their press release, which seems a safe assumption. We can also assume that some of the "year unknown" movies on the bottom tier, like Thor 3 and Gambit, may eventually be placed in some of the existing slots in the timeline, and that Marvel Studios, Fox, and Sony Columbia will announce further dates in 2019 and 2020.
Make sure to check out the entire story with their analysis here.