New hook - pycparser

Packaging without this hook generates an executable that seems to work.

However, on running, pycparser generates the lextab.py and yacctab.py modules. This may fail in cases where the executable has no permissions to write wherever it wants to write: which seems to be the same directory as the remaining packaged binaries.

Having no knowledge of pycparser itself (I'm using it as a dependency for cffi which, in turn, is a dependency for cryptography) I'm not sure if this is the optimal approach or if somehow the runtime generated modules are preferrable.

Feedback is welcome.