Add a calendar to the Show view.

Still needs:
 - Show links
 - Color coding
 - Other CSS tweaks (e.g. extra space between calendar and list)
Merge branch 'develop' into feature/show_calendar
Link to all shows on the member mini calendar (not just shows we have shifts for)
Merge branch 'develop' into feature/show_calendar
Merge branch 'develop' into feature/show_calendar
refactor show_calendar into partial
Added JS to scroll to show line and back to top when links clicked.
ignore pow files
Add styling to show calendar
Merge branch 'feature/show_calendar' into develop