VCD scene files for scenes.image building

Because the SteamPipe update removed the .vcd files for scenes, it's not possible anymore to rebuild scenes.image in Faceposer, so partial mods (that use both Valve's and custom scenes) cannot be created.

In this pull request, I added the VCDs for Half-Life 2, Episode One, Episode Two, Lost Coast and Portal to /sp/game from the pre-SteamPipe GCF files. The Orange Box scenes for Half-Life 2 and Episode One are applied.

The files are not in the "mod_" folders because they are not required to create a mod from scratch and to avoid confusion between Episode One and Episode Two.