vrfs-768: changed url param for admin toggle to just admin; added h2 title with instructions for toggling

admin/Gemfile

@@ -79,7 +79,7 @@ end
 # gem 'capistrano'
 
 # To use debugger
-# gem 'debugger'
+gem 'debugger'
 
 group :development, :test do
   gem 'capybara'

admin/app/admin/music_session_history.rb

@@ -6,7 +6,7 @@ ActiveAdmin.register JamRuby::MusicSessionHistory, :as => 'Music Session History
 
   controller do
     def scoped_collection
-      if '1' == params['user_admin_eq']
+      if params['admin'].blank? || '1' == params['admin']
         @music_session_histories ||= end_of_association_chain
           .includes([:user, :band])
           .order('created_at DESC')
@@ -23,6 +23,7 @@ ActiveAdmin.register JamRuby::MusicSessionHistory, :as => 'Music Session History
   index :as => :block do |msh|
     div :for => msh do
       h3 "Session ##{msh.music_session_id}: #{msh.created_at.strftime('%b %d %Y, %H:%M')}"
+      h4 "(append URL with ?admin=0 to hide admin sessions)"
       columns do
         column do
           panel 'Session Details' do