Prevent crash when standards-report dir doesn't exist
Fix build-time hard-coded path introduced by the guile2 compile changes

These changes hardcoded the standards-reports path at build time.
On Windows and OS X the final path is only known at installation time.
So after installation the build-time hard-coded path would be invalid and
the standard-reports directory could no longer be found.
Fix a few typos in python example scripts and align them with the latest api changes
Python bindings - fix creation of new xml files