Moved test Vagrantfile to a dedicated directory
 * Doing so enable us to reduce filename lengths by removing the
   Vagrantfile prefix.
Fixes #9
 * The keys stored in a Bag are always normalized to a symbol. Each method
   receiving a key now normalize it to a symbol for comparaison within
   the bag.
 * Fixed tests to always test all access type which would have shown
   this problem before.
Updated CHANGELOG