Refactoring Tickets

- Tickets now independent from registration
- Implemented money gem
#419

app/views/tickets/index.html.haml

@@ -0,0 +1,37 @@
+.row
+  .col-sm-12.col-md-10.col-md-offset-1
+    %h1
+      Tickets
+    %p.lead
+      Please buy a ticket if you want to support
+      %b
+        = @conference.title
+        !
+    =form_tag(conference_ticket_purchases_path, method: :post) do |f|
+      %table.table.table-hover
+        %thead
+          %tr
+            %th Ticket
+            %th Quantity
+            %th Price
+            %th Total
+        %tbody
+          - @conference.tickets.each do |ticket|
+            = render partial: 'ticket', f: f, locals: {ticket: ticket}
+          %tr
+            %td
+            %td
+            %td.col-sm-1.col-md-1.text-center
+              %h4
+                Total
+            %td.col-sm-1.col-md-1.text-center
+              %h4
+                %strong
+                  %span{id: 'total_price'}
+                    0
+      .pull-right
+        = button_tag(type: 'submit', class: 'btn btn-success btn-lg') do
+          Support
+          %i.fa.fa-shopping-cart
+        = link_to 'Continue without a Ticket!', conference_conference_registrations_path(@conference.short_title),
+        class: 'btn btn-danger btn-sm'