fixed e.c. isogeny classes for Sage version 6.2+
Merge branch 'master' of https://github.com/LMFDB/lmfdb
Merge branch 'master' of https://github.com/LMFDB/lmfdb
Merge branch 'master' of https://github.com/LMFDB/lmfdb
Merge branch 'master' of https://github.com/LMFDB/lmfdb
Merge branch 'master' of github.com:LMFDB/lmfdb
Merge branch 'master' of github.com:JohnCremona/lmfdb
Merge branch 'master' of github.com:LMFDB/lmfdb
Merge pull request #148 from JohnCremona/master

fixed e.c. isogeny classes for Sage version 6.2+