[#289] Add select action and view
Merge pull request #207 from gotar/289-contest-controller-select-action

[#289] Add select action and view
[237] contest show renders new competition form
Merge pull request #212 from gotar/237-contest-show-to-render-new-competition-form

[237] contest show renders new competition form
[#295] Add checkbox to delete second_address if present
Clean unnecessary code from js
Make additional_address checkbox disabled and checked if second_address is present