Make the error message more understandable
Delete key from the pending request
Remove the unnecessary command flags
Show help if there is no key to be imported/deleted
Remove an obsolete option from the man page
Add the new option to clear MOK password
Add new option to list the keys to be deleted

Also restructure the key list function
Rework the salt generation function
Support the old password hash method

For MokManager without the password crypt patch, "--simple-hash"
was added to be compatible with the old password hash.
Update manpage
Add Copyright headers
Version bump to 0.2.0