Release 15.0.0

Feature: New Callback Mechanism with support for IL2CPP (Thanks to @GMMan)
Feature: Update to Steamworks SDK 1.51

Fixed: UTF8 strings inside structs are no longer corrupted. (#339, #347) (Thanks to @Akarinnnnn)
Fixed: Renamed SteamRemoteplay folder to SteamRemotePlay (#374)
Fixed: Debug info no longer causes build to fail if it occurs before plugins get copied. (#350)
Fixed: Opt into supported Unity platforms rather than opting out of them. (#342)

Get the .unitypackage if you are using Unity.
The prebuilt "Standalone" package is for non-Unity projects ONLY.