Added support for LZMA2 compression method in .7z archives

Updated LZMA SDK to version 9.20
http://www.7-zip.org/sdk.html
http://downloads.sourceforge.net/sevenzip/lzma920.tar.bz2
Fixed file list in VS2005 project of LZMA library
Fixed compilation with updated LZMA library using Visual Studio
Merge branch 'master' of https://github.com/rheit/zdoom into lzma2