Initialise 'padding'

I don't like random data appearing in output. Even if it's redundant.
Specify which exceptions can be handled in a 'try...except...' statement.
Ensure that all strings are at least 1 char in pack.sh

Fortran does not allow CHARACTER strings to have a length less
than one. This was already fixed in "pack.py" but not in "pack.sh".

This fixes FGE bug-tracker issue 158
Options for packing source code set from CMake...

...this probably breaks the Makefile.
Merge remote branch 'origin/master' into mbda
Merge remote-tracking branch 'mbda/mbda' into mbda
Fixed GIT_DIR variable and a Python exception.