Returns the preferred filename extension for the specified Uniform Type Identifier.
Original signature is '- (NSString *)preferredFilenameExtensionForType:(NSString *)typeName'
Available in Mac OS X v10.5 and later.


- typeName (NSString)
- A string containing the Uniform Type Identifier.

The appropriate filename extension for typeName, or nil if no extension could be determined.

- Available in Monobjc Bridge: 10.6 (For Mac OS X 10.6 and later), 10.5 (For Mac OS X 10.5 and later)