This is a partly solution for TAP5-815 (only for *.properties files).
Also for 'jar' and 'xml' a digest should be created.
This is not a solution, not even partly, for TAP-815 because, as far as I know, the problem source is that the digest is not checked in some circunstances (virtual versioned assets).
Event if it is not a solution for TAP-815, we should add these extensions. If we add 'class' and 'tml', we also should add 'jar' and 'xml'.