0006410: Webcal report crashes and freezes alpha4. For python3 simply opening the file works.

git-svn-id: svn+ssh://svn.code.sf.net/p/gramps/code/trunk@21458 4ae1f11a-8b86-4847-b8af-ab372f36d1fd
6409 and 6447 Python3 changes (possibly not done yet)

git-svn-id: svn+ssh://svn.code.sf.net/p/gramps/code/trunk@21459 4ae1f11a-8b86-4847-b8af-ab372f36d1fd
Fix type error in "python3 Gramps.py -L"

git-svn-id: svn+ssh://svn.code.sf.net/p/gramps/code/trunk@21461 4ae1f11a-8b86-4847-b8af-ab372f36d1fd
Fix retrieval of version metadata for python3 Gramps.py -L

git-svn-id: svn+ssh://svn.code.sf.net/p/gramps/code/trunk@21464 4ae1f11a-8b86-4847-b8af-ab372f36d1fd