work on sign in tensor product
Do the semistable x semistable correctio
fix typo
add comment
Merge branch 'master' of https://github.com/MarkWatkins2014/lmfdb into mine

* 'master' of https://github.com/MarkWatkins2014/lmfdb:
  add comment
  fix typo
  Do the semistable x semistable correctio
small change to mark's corrections at nasty primes