SOFTHSM-66: Make the OSAttribute read only
SOFTHSM-66: Add new interface for getting boolean and unsigned long values
SOFTHSM-66: Add getByteStringValue() to objects and adjust DB code to handle attributes correctly.
SOFTHSM-66: Return a copy of the value when using getAttribute()
SOFTHSM-66: Use the new interface
SOFTHSM-66: Update the NEWS
Merge branch 'SOFTHSM-66' of https://github.com/bellgrim/SoftHSMv2 into bellgrim-SOFTHSM-66

Conflicts:
	NEWS
Merge branch 'bellgrim-SOFTHSM-66' into develop
https://github.com/opendnssec/SoftHSMv2/pull/86