integrate 'construct' python library

'construct' is a declarative symmetric encoder/decoder for user
specified binary formats.  It should come in extremely handy in
tools like pySim.

We start the integration by adding transport methods for transceiving
APDUs with built-in encoding of the command data and decoding of the
response data.

Change-Id: Ibf457aa8b9480a8db5979defcfafd67674303f6c

contrib/jenkins.sh

@@ -15,6 +15,7 @@ pip install pytlv
 pip install pyyaml
 pip install cmd2
 pip install jsonpath-ng
+pip install construct
 
 # Execute automatically discovered unit tests first
 python -m unittest discover -v -s tests/