Web interface: Use bigger thumbnails by default

This doesn't change what they become when the DOM loads since JavaScript takes over, but this should improve things before then, which can be several seconds
Web interface: Improved client-side performance
Formatting
Merge branch 'master' of github.com:UniversalMediaServer/UniversalMediaServer into 5.0.0

Conflicts:
	src/main/external-resources/web/jquery.ums.js
	src/main/external-resources/web/web.css
	src/main/java/net/pms/dlna/DLNAResource.java