[core] allow eventual consistency in wait_for

closes #102

lib/fog/aws/models/compute/server.rb

@@ -167,7 +167,7 @@ module Fog
               Timeout::timeout(4) do
                 Fog::SSH.new(ip_address, username, credentials).run(commands)
               end
-            rescue Timeout::Error
+            rescue Net::SSH::AuthenticationFailed, Timeout::Error
               retry
             end
           end

lib/fog/aws/models/compute/servers.rb

@@ -98,19 +98,7 @@ module Fog
           end
 
           server.save
-          # eventual consistency sometimes means a delay before it appears
-          retries = 3
-          begin
-            server.wait_for { ready? }
-          rescue Fog::Errors::Error => error
-            sleep(1)
-            retries -= 1
-            if retries > 0
-              retry
-            else
-              raise error
-            end
-          end
+          server.wait_for { ready? }
           server.setup(:key_data => [server.private_key])
           server
         end

lib/fog/core/model.rb

@@ -39,7 +39,15 @@ module Fog
     def wait_for(timeout=600, interval=1, &block)
       reload
       Fog.wait_for(timeout, interval) do
-        reload or raise Fog::Errors::Error.new("Reload failed, #{self.class} #{self.identity} went away.")
+        retries = 3
+        if reload
+          retries = 3
+        elsif retries > 0
+          retries -= 1
+          sleep(1)
+        elsif retries == 0
+          raise Fog::Errors::Error.new("Reload failed, #{self.class} #{self.identity} went away.")
+        end
         instance_eval(&block)
       end
     end