[12gevmoller_sim] [EXTERNAL] [JeffersonLab/remoll] 745f18: Change mother volume to air

[rahmans1]

  Branch: refs/heads/test-hevac
  Home:   https://urldefense.proofpoint.com/v2/url?u=https-3A__github.com_JeffersonLab_remoll&d=DwICaQ&c=CJqEzB1piLOyyvZjb8YUQw&r=-0uahHXTLsQsllHBZNHgOynLaY6DUxqehsUJ91-BlNY&m=CuVLpsX90J_C2d9V9TeFTucv1UB-dWxKXmGn8R-76cU&s=t3QjG9lj05pcCpCvoPFTujRXDUmMDesQunh1Xl6w9Wk&e= 
  Commit: 745f187955b445a0105bc55193191ae45ad57780
      https://urldefense.proofpoint.com/v2/url?u=https-3A__github.com_JeffersonLab_remoll_commit_745f187955b445a0105bc55193191ae45ad57780&d=DwICaQ&c=CJqEzB1piLOyyvZjb8YUQw&r=-0uahHXTLsQsllHBZNHgOynLaY6DUxqehsUJ91-BlNY&m=CuVLpsX90J_C2d9V9TeFTucv1UB-dWxKXmGn8R-76cU&s=MvrKnO-EP7b2jrjHcjrUo1xj1FAYLO9-R9NxPlDxPa8&e= 
  Author: Sakib <srahman at sapsimserv.physics.umanitoba.ca>
  Date:   2019-12-02 (Mon, 02 Dec 2019)

  Changed paths:
    M geometry/mollerMother_merged.gdml

  Log Message:
  -----------
  Change mother volume to air