Loads correct screen after author refreshes page in editor
Loads correct screen after author refreshes page in editor

closes #4415
- corrected logic around author check
- fixes a bug where it was possible to see editor for other author posts

TryGhost/Ghost-Admin,dbalders/Ghost-Admin,acburdine/Ghost-Admin,JohnONolan/Ghost-Admin,airycanon/Ghost-Admin,TryGhost/Ghost-Admin,kevinansfield/Ghost-Admin,airycanon/Ghost-Admin,dbalders/Ghost-Admin,acburdine/Ghost-Admin,kevinansfield/Ghost-Admin,JohnONolan/Ghost-Admin