Drop unused CI tables and files

These tables, web hooks and services, are unused but where not dropped
with the commits d5c91bb9 and
2988e1fb.

The file was left too, but never called.

app/services/ci/web_hook_service.rb

-module Ci
-  class WebHookService
-    def build_end(build)
-      execute_hooks(build.project, build_data(build))
-    end
-
-    def execute_hooks(project, data)
-      project.web_hooks.each do |web_hook|
-        async_execute_hook(web_hook, data)
-      end
-    end
-
-    def async_execute_hook(hook, data)
-      Sidekiq::Client.enqueue(Ci::WebHookWorker, hook.id, data)
-    end
-
-    def build_data(build)
-      project = build.project
-      data = {}
-      data.merge!({
-        build_id: build.id,
-        build_name: build.name,
-        build_status: build.status,
-        build_started_at: build.started_at,
-        build_finished_at: build.finished_at,
-        project_id: project.id,
-        project_name: project.name,
-        gitlab_url: project.gitlab_url,
-        ref: build.ref,
-        before_sha: build.before_sha,
-        sha: build.sha,
-      })
-    end
-  end
-end

db/migrate/20160824103857_drop_unused_ci_tables.rb

+class DropUnusedCiTables < ActiveRecord::Migration
+  include Gitlab::Database::MigrationHelpers
+
+  # Set this constant to true if this migration requires downtime.
+  DOWNTIME = false
+
+  def change
+    drop_table(:ci_services)
+    drop_table(:ci_web_hooks)
+  end
+end

db/schema.rb

@@ -11,7 +11,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema.define(version: 20160823081327) do
+ActiveRecord::Schema.define(version: 20160824103857) do
 
   # These are extensions that must be enabled in order to support this database
   enable_extension "plpgsql"
@@ -295,16 +295,6 @@ ActiveRecord::Schema.define(version: 20160823081327) do
   add_index "ci_runners", ["locked"], name: "index_ci_runners_on_locked", using: :btree
   add_index "ci_runners", ["token"], name: "index_ci_runners_on_token", using: :btree
 
-  create_table "ci_services", force: :cascade do |t|
-    t.string   "type"
-    t.string   "title"
-    t.integer  "project_id",                 null: false
-    t.datetime "created_at"
-    t.datetime "updated_at"
-    t.boolean  "active",     default: false, null: false
-    t.text     "properties"
-  end
-
   create_table "ci_sessions", force: :cascade do |t|
     t.string   "session_id", null: false
     t.text     "data"
@@ -360,13 +350,6 @@ ActiveRecord::Schema.define(version: 20160823081327) do
 
   add_index "ci_variables", ["gl_project_id"], name: "index_ci_variables_on_gl_project_id", using: :btree
 
-  create_table "ci_web_hooks", force: :cascade do |t|
-    t.string   "url",        null: false
-    t.integer  "project_id", null: false
-    t.datetime "created_at"
-    t.datetime "updated_at"
-  end
-
   create_table "deploy_keys_projects", force: :cascade do |t|
     t.integer  "deploy_key_id", null: false
     t.integer  "project_id",    null: false