use find_or_create_by to avoid duplicate / validation failing records when running rake db:seed
seeds no longer references removed(???) column
added installation instructions
add pry-rails to development, test groups because awesome
display event start, event end on form
vol ops controller translates datetimepicker string to Ruby DateTime
refactor event start / end handling code

now on edit page gives date time picker format it wants; post processing code in separate function
Merge branch 'rwilcox-datetime_picker_changes'