Update to for DProperties PKCS#11/MSCAPI providers

[jonwltn]

This PR updates DProperties so that it does not show PKCS#11 or MSCAPI private keys as locked. It includes the following improvements:

• Don't indicate that PKCS#11 and MSCAPI private keys are locked.
• Display the curve for EC keys.
• Automatically unlock key entries for PKCS#12 and PEM key stores, if possible.

Added the EC curve:

This is what MSCAPI private EC key looks like:

RSA key:

I should probably be consistent with the key sizes. Previously, DProperites just showed "Locked - unload to get properites", which isn't totally true, but it hid all the unknown details. Perhaps for the PKCS#11 private keys, it would be better to state that the key details are protected.

Finally, I noticed that for RSA and DSA keys DProperties displays the key parameters/fields, but it does not do that for all the new key pair types that have been added. Do you want to include all the private/public key fields in DProperties, too?

[kaikramer]

I should probably be consistent with the key sizes. Previously, DProperites just showed "Locked - unload to get properites", which isn't totally true, but it hid all the unknown details. Perhaps for the PKCS#11 private keys, it would be better to state that the key details are protected.

Sounds reasonable.

Finally, I noticed that for RSA and DSA keys DProperties displays the key parameters/fields, but it does not do that for all the new key pair types that have been added. Do you want to include all the private/public key fields in DProperties, too?

I could imagine scenarios where this might be useful in combination with the text export (the "Copy" button) to get a list of the keys in the keystore with details - if there are more than a couple of keys in it. But I think this is a rather exotic use case and it should be very low on the priority list.

[jonwltn]

I'm still working on this.

[jonwltn]

This resolves the EC and RSA inconsistencies for protected private keys.

This one is ready for final review and comments.