In smart cards, we every so often encounter data types that contain a
bit-mask whose length depends on whether or not there are any of the
least-significant bits are set. So far we worked around this with
some kind of Struct('byte1', 'byte2'/COptional, 'byte3'/COptional)
approach.
Let's do thisin a generic way using the new StripTrailerAdapter.
Change-Id: I659aa7247c57c680895b0bf8412f9e477fc3587d
7156a40187