added description field to cfps

closes #1650

done some changes

minor changes

added markdown format to cfp#show

fixed description text  position in proposals

fixed truncated description text in show action

minor changes on non-admin side

db/migrate/20170905110034_add_description_to_cfps.rb

@@ -0,0 +1,5 @@
+class AddDescriptionToCfps < ActiveRecord::Migration
+  def change
+    add_column :cfps, :description, :text
+  end
+end

db/schema.rb

@@ -68,12 +68,13 @@ ActiveRecord::Schema.define(version: 20170924190528) do
   end
 
   create_table "cfps", force: :cascade do |t|
-    t.date     "start_date", null: false
-    t.date     "end_date",   null: false
+    t.date     "start_date",  null: false
+    t.date     "end_date",    null: false
     t.datetime "created_at"
     t.datetime "updated_at"
     t.integer  "program_id"
     t.string   "cfp_type"
+    t.text     "description"
   end
 
   create_table "comments", force: :cascade do |t|