Implement missing p11mod functions #128
Description
A lot of functions that exist in pkcs11mod are unimplemented in p11mod. The easy way to find them is by grepping p11mod.go for CKR_FUNCTION_NOT_SUPPORTED. It would be desirable to implement them.
Note that some of those functions may be impossible to implement due to limitations of the p11 API. There are plenty that will work fine though, so if you see one that looks problematic, pick another one -- lots of low-hanging fruit.