Merge pull request #1822 from arnova/album_thumb_fix

fixed: Different (file) items with the same artist/album name could over...
jsonrpc: add "displayartist" property to albums and songs
musicdb: fix retrieval of compilation flag for songs
musicdb: add strAlbumArtists to songview for fast retrieval
json-rpc: add "albumartistid" property for songs
Merge pull request #1840 from Montellese/jsonrpc_artist_mess

jsonrpc: add "genreid", "artistid", "albumartistid" and "displayartist" to songs and albums and fix "albumartist" for songs
jsonrpc: add missing fields and properties to List.* types and clean them up
fixed: reimplementing Latin1StringHandler.parse() to get non-ISO-8859-1 tags correctly
Merge pull request #1851 from taxigps/taglib

fixed: reimplementing Latin1StringHandler.parse() to get non-ISO-8859-1 ...
jsonrpc: use CFileItemPtr instead of CFileItem in FillFileItem() to fix crashes
cosmetics: get rid of unused variable
library: add method to determine season num from episode id
upnp: fix container updates for episodes where seasons > 1
[AE/CA] - fix upmix of source formats which don't have a 4byte frame size (e.x. 16bit integer as received from airtunes) - thx gimli for backing most of these commits :)
[CA/AE] - fix passthrough - don't start the engine before stream initialisation
NFSDirectory.cpp must include limits.h
Merge pull request #1854 from tkurbad/nfslib-fix

NFSDirectory.cpp must include limits.h
[osx/ios] - save the sinkname instead of the device label to guisettings.xml (somehow we forgot about darwin when that was changed...)
[win32] fix log message on failed call to D3DXCreateEffect
make backspace go back in music vis as it does in fullscreen video