#39 LZMA/XZ MIME type support

[Kevin Kofler]

This patch is more or less a followup to patch 2873567. It adds default protocol handlers for application/x-lzma (.lzma), application/x-xz (.xz, requires KrArc support from patch 2873567), application/x-lzma-compressed-tar (.tar.lzma) and application/x-xz-compressed-tar (.tar.xz).

[Kevin Kofler]

Add LZMA and XZ handlers