Package check result: NOTE

Check: CRAN incoming feasibility, Result: NOTE
  Maintainer: ‘Zehao Xu <z267xu@gmail.com>’
  
  New maintainer:
    Zehao Xu <z267xu@gmail.com>
  Old maintainer(s):
    Zehao Xu <z267xu@uwaterloo.ca>

No changes to worse in reverse depends.