Put event name back to installation

It seems GitHub is currently sending both apps events
twice, under different names.

When we get confirmation about the correct names from them,
this is ready to merge.

Author: joecorcoran

lib/travis/listener/app.rb

@@ -23,7 +23,7 @@ class App < Sinatra::Base
         create
         delete
         repository
-        integration_installation
+        installation
         installation_repositories
       ]
 
@@ -110,7 +110,7 @@ def github_pr_event?
 
       def github_apps_event?
         [
-          'integration_installation',
+          'installation',
           'installation_repositories',
         ].include? event_type
       end
@@ -138,7 +138,7 @@ def sync_event
         )
 
         case event_type
-        when 'integration_installation'
+        when 'installation'
           Travis::Sidekiq::GithubSync.gh_app_install(data)
         when 'installation_repositories'
           Travis::Sidekiq::GithubSync.gh_app_repos(data)

spec/payloads/integration_installation.json renamed to spec/payloads/installation.json

@@ -14,7 +14,7 @@
   before { create }
 
   def create(opts = {})
-    if ["integration_installation", "installation_repositories"].include? type
+    if ["installation", "installation_repositories"].include? type
       params = payload
     else
       params = { :payload => (opts[:payload] || payload) }
@@ -90,9 +90,9 @@ def create(opts = {})
     include_examples 'queues gatekeeper event'
   end
 
-  describe 'an integration_installation event' do
-    let(:type)  { 'integration_installation' }
-    let(:event) { 'integration_installation' }
+  describe 'an installation event' do
+    let(:type)  { 'installation' }
+    let(:event) { 'installation' }
 
     it { expect(gh_sync_queue)
       .to have_received(:push)