vdr-plugin-text2skin

Changes:

- New tokens: UsedDiskSpace, TotalDiskSpace, VideoSizeWidth, VideoSizeHeight
  (closes #465, thanks to NemoN).
- Documentation fixes.
- Commit t2s_rerunandtab.diff by tomas@vdr-portal.de
  http://www.vdr-portal.de/board17-developer/board25-patches/p914968-patch-f%C3%BCr-text2skin-channelnames4reruns/#post914968
- Commit common_c.diff most probably by Christian Winninger (unknown source)
- Commit status_c.diff most probably by Gerald Dachs (unknown source)
- Commit static-std-string.diff by Lars Hanisch (unknown source)
- Commit text2skin-signal.patch by tomas@vdr-portal.de (unknown source)
- Commit text2skin-vdr2.1.2compat.diff by Christopher Reimer (unknown source)
- New version reflecting VDR 2.2.0 compatibility