add booth in alias

Booth can be replaced with any alias by replacing it in alias.en.yml.

app/views/conferences/_booths.haml

@@ -1,6 +1,6 @@
 .row
   .col-md-12
-    %h3.text-center Booths
+    %h3.text-center "#{(t'booth').pluralize.capitalize }"
 .row.row-centered
   - booths.each do |booth|
     .col-md-2.col-sm-2.col-centered.col-top.booth

app/views/conferences/_call_for_booths.haml

@@ -1,12 +1,12 @@
 - cache [conference_id, call, '#splash#callforbooths'] do
   .col-md-4.col-sm-4.text-center
     %h2
-      Call for Booths
+      Call for #{(t'booth').pluralize.capitalize }
     %p.lead
-      We are now accepting custom booth requests!
+      We are now accepting custom #{t'booth'} requests!
     %p
-      Would you like to request a new booth?
-      The submission period for booth requests is open
+      Would you like to request a new #{t'booth'}?
+      The submission period for #{t'booth'} requests is open
       %em
         = date_string(call.start_date, call.end_date) + '.'
       %b
@@ -14,6 +14,6 @@
         = pluralize(call.remaining_days, 'day')
         left!
     %p.cta-button
-      = link_to("Submit your request for booth",
+      = link_to("Submit your request for #{t'booth'}",
         new_conference_booth_path(conference_id),
         class: 'btn btn-success btn-lg text-center')

app/views/conferences/_conference_details.html.haml

@@ -44,9 +44,9 @@
               - if conference.program.cfp_open?
                 = link_to "Submit Proposal", new_conference_program_proposal_path(conference.short_title), class: 'btn btn-default'
             - if current_user && current_user.booths.where(conference_id: conference.id).count > 0
-              = link_to 'My Booth Requests', conference_booths_path(conference.short_title), class: 'btn btn-default'
+              = link_to "My #{(t'booth').capitalize } Requests", conference_booths_path(conference.short_title), class: 'btn btn-default'
             - elsif can? :new, conference.booths.new
-              = link_to 'Request Booth', new_conference_booth_path(conference.short_title), class: 'btn btn-default'
+              = link_to "Request #{(t'booth').capitalize }", new_conference_booth_path(conference.short_title), class: 'btn btn-default'
             - if current_user.nil? || !current_user.subscribed?(conference)
               = link_to 'Subscribe', conference_subscriptions_path(conference.short_title), method: :post, class: 'btn btn-default'
             - else