Revert "allow symbol or string for top level compute/storage"

This reverts commit 7446988.

all the other config is strings, leave them this way for consistency

lib/fog/core/compute.rb

@@ -2,26 +2,26 @@ module Fog
   class Storage
 
     def self.new(attributes)
-      case attributes.delete(:provider).to_sym
-      when :AWS
+      case attributes.delete(:provider)
+      when 'AWS'
         require 'fog/aws'
         Fog::AWS::Compute.new(attributes)
-      when :Bluebox
+      when 'Bluebox'
         require 'fog/bluebox'
         Fog::Bluebox::Compute.new(attributes)
-      when :GoGrid
+      when 'GoGrid'
         require 'fog/go_grid'
         Fog::GoGrid::Compute.new(attributes)
-      when :Linode
+      when 'Linode'
         require 'fog/linode'
         Fog::Linode::Compute.new(attributes)
-      when :NewServers
+      when 'NewServers'
         require 'fog/new_servers'
         Fog::NewServers::Compute.new(attributes)
-      when :Rackspace
+      when 'Rackspace'
         require 'fog/rackspace'
         Fog::Rackspace::Compute.new(attributes)
-      when :Slicehost
+      when 'Slicehost'
         require 'fog/slicehost'
         Fog::Slicehost::Compute.new(attributes)
       else

lib/fog/core/storage.rb

@@ -2,17 +2,17 @@ module Fog
   class Storage
 
     def self.new(attributes)
-      case provider = attributes.delete(:provider).to_sym
-      when :AWS
+      case provider = attributes.delete(:provider)
+      when 'AWS'
         require 'fog/aws'
         Fog::AWS::Storage.new(attributes)
-      when :Google
+      when 'Google'
         require 'fog/google'
         Fog::Google::Storage.new(attributes)
-      when :Local
+      when 'Local'
         require 'fog/local'
         Fog::Local::Storage.new(attributes)
-      when :Rackspace
+      when 'Rackspace'
         require 'fog/rackspace'
         Fog::Rackspace::Storage.new(attributes)
       else