Classes: BundleSigner, BundleVerifier, SignUtility, SignatureFile
The BundleSigner class is used sign an existing
bundle, using a digital signature algorithm
based on the RSA and SHA1 message digest algorithms. 
The BundleVerifier class is used to verify the
signature of a signed bundle.
This class is used to compute hash digests
for the files in a bundle.
This class is used to compute hash digests
for the files in a bundle.