Fixing some tests that weren't testing correctly

These assertions were always returning true even if you dont populate
the flash, because nil.should_not be_empty returns true

spec/controllers/aspect_memberships_controller_spec.rb

@@ -59,7 +59,7 @@ describe AspectMembershipsController do
         :format => 'js',
         :person_id => @person.id,
         :aspect_id => @aspect0.id
-      flash[:error].should_not be_empty
+      flash[:error].should_not be_blank
     end
 
     it 'does not 500 on a duplicate key error' do

spec/controllers/invitations_controller_spec.rb

@@ -162,7 +162,7 @@ describe InvitationsController do
     it 'displays a message that tells the user how many invites were sent, and which REJECTED' do
       post :create, :user => @invite.merge(
         :email => "mbs@gmail.com, foo@bar.com, foo.com, lala@foo, cool@bar.com")
-      flash[:notice].should_not be_empty
+      flash[:notice].should_not be_blank
       flash[:notice].should =~ /foo\.com/
       flash[:notice].should =~ /lala@foo/
     end

spec/controllers/profiles_controller_spec.rb

@@ -39,7 +39,7 @@ describe ProfilesController do
           :first_name => "Will",
           :last_name  => "Smith"
         }
-      flash[:notice].should_not be_empty
+      flash[:notice].should_not be_blank
     end
 
     it 'sets tags' do

spec/controllers/registrations_controller_spec.rb

@@ -61,7 +61,7 @@ describe RegistrationsController do
 
       it "sets the flash" do
         get :create, @valid_params
-        flash[:notice].should_not be_empty
+        flash[:notice].should_not be_blank
       end
 
       it "redirects to the home path" do