Release 4.4.0

Changed

• Throw a descriptive exception when trying to load a non-existant key from
  HSM
• A huge chunk of code was moved from hsm-example.cpp to
  tests/integration/hsm-integration-test.cpp where keys loaded/generated on HSM
  are used for various cryptopgraphic algorithms
• Creating multiple keys with the same ID on the HSM is now not possible.
• libp11 patch was modified to support a custom PKCS#11 implementation which
  does not implement all the PKCS#11 features as defined by the standard

Fixed

• Creating multiple HsmEngine in a row has overwritten a set PIN from the
  previous one due to shared state in libp11. This caused problems when logging
  in to the token. This has been fixed.
• PKCS#11 URIs are used to identify which key to fetch from the HSM.
  Construction of this URI didn't take into account PKCS#11 URI special
  characters that need to get escaped in order to avoid accidental or malicious
  construction of invalid PKCS#11 URI. The special characters have been escaped.

Added

• utility::stringCleanse function was added for safely clearing a std::string
  object