added tokens {month}, {monthname} and {year} in displaymenutimers listitem and currentitem
added dedicated tokens for posters and banners in <srapercontent> in displaychannel and displayreplay
Merge branch 'master' of git://projects.vdr-developer.org/vdr-plugin-skindesigner
Updated documentation

- Updated information about dependencies
- Fixed line lengths to look better when viewed on shell
- Removed some trailing whitespaces