Revert "Switched URL action button to UIActivityController" et al.

Not convinced it's the right way to go, and it really does look awful. Worth
revisiting, not ready now.

This reverts commit db5acb9daa8f6858dac5429821f4909fb9df9cdd.
This reverts commit cb9063806a8860988aac00de96a73832bfb3147d.
This reverts commit faabeaa5f4393abc032c78eb78b98d88b6ce2b7a.
This reverts commit 1f0ef3e27b0e211c76f2977391c6fb97bad55624.