Escape regex special characters in tag finder
Escape regex special characters in tag finder

refs #2149
- Properly highlight tags with special characters ($,[,],^,etc.)

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