Create quick hashes of files
Add support for full MD5 hash

Refactor code for checking mediasource availability
Calculate hash from MediaSource instead of WebFileInfo
Libraries: Move ToHexString() extension method to global util library
WSS: Move hash computation code to MediaSource class

Doesn't make much sense to have extension methods for a class in the same
namespace as the class itself.
WSS: Make streaming support status messages translatable

Also some code cleanup in the service itself.
Merge branch 'wss-filehashes'
WSS: Add method to request resizing of an image before loading it

This can be used to already resize pictures the user is expected to open later on, to
decrease the latency.
Merge branch 'eve-request-image-cache'

Conflicts:
	Services/MPExtended.Services.StreamingService.Interfaces/IWebStreamingService.cs