[URIUtils] Fix IsSmb, IsFTP, IsAfp, IsDAV and IsNfs.

Due to protocol stacking, e.g., files in a zip on a smb share were not recognized as files on a network share.

There might be more is* methods that could benefit from analogue changes.
@Karlson2k for review
Don't we need to url-decode in this case?
And in similar places below.