Unreal Tournament v469c - Release Candidate 4

This build fixes the last remaining high-priority issues before the final release of v469c. Changes since RC3 include:

• Fixed a bug that made UnrealEd discard the alpha channel while importing BC7-compressed textures
• Fixed a bug that made UnrealEd duplicate actors when undoing an actor paste operation
• Fixed an XOpenGLDrv problem that made certain weapons render on top of the HUD
• The IpDrv.InternetLink class now has a TextEncoding variable. This variable controls the behavior of text transmitting and receiving functions in InternetLink subclasses. Please refer to the comments in the IpDrv.InternetLink source code for further documentation
• Windows raw mouse input now also works in windowed mode
• The web admin and udp server query protocol can now transmit information in UTF-8 format. As a result, Unicode playernames, chat messages, etc. should now appear correctly
• Fixed a crash while rendering weapons with scripted ammo counters (e.g. pulse gun, flak cannon) on Intel Macs
• Fixed an issue that could make the macOS client wipe the game ini

Note: The web admin and query protocol currently transmit unicode characters as UTF-8 sequences, but the in-game server browser still assumes the information it receives is in plain ANSI. The browser will, therefore, still not correctly show unicode characters it receives from servers. We will try to fix this in 469d.