Fix NPEs
Custom device configurations
[1/4] Allow device configurations to override PmsConfiguration
[2/4] Use non-static PmsConfiguration in DLNAResource classes
[3/4] Use non-static PmsConfiguration in Player classes
[4/4] Use non-static PmsConfiguration in request and process classes
Remove redundant common getters
Device configuration: shared folders
Device configuration: transcode folders
Device configuration: WEB.conf