Revert "When downloading iOS app, don't delete session during the HEAD request."

This reverts commit 31ff3916c2d789ea93381b4ae0e16247bf40c8de.
Revert "Add API method to delete an application version. Allow DELETE methods in Swagger."

This reverts commit 9d2aeda7d4168d92a22272131283699d88cf5df7.
Revert "fix whitespace"

This reverts commit aa92eaf001fa0fc6e4d3337aee72316b2701bf8a.
Revert "Revert "fix whitespace""

This reverts commit e52ad561cd57817d2d9a998bda9f12476e1f59ef.