use first plan listed, instead of assuming 100

lib/harness/service.rb

@@ -42,20 +42,24 @@ def create(service_manifest, check_available = true)
       end
       @log.debug("Prepare to create service: #{@instance.name}")
       begin
+        plans = service.service_plans
+
         if service_manifest[:plan]
           plan = service_manifest[:plan]
         elsif ENV['VCAP_BVT_SERVICE_PLAN']
           plan = ENV['VCAP_BVT_SERVICE_PLAN']
+        elsif @session.v2?
+          plan = plans.first.name
         else
-          plan = @session.v2? ? "100" : "free"
+          plan = "free"
         end
+
         if @session.v2?
-          plans = service.service_plans.select { |p| p.name == plan}
+          plans = plans.select { |p| p.name == plan }
           if plans.size == 0
-            plan_list = []
-            service.service_plans.each {|p| plan_list << p.name}
-            @log.error("can't find service plan #{plan}, supported plans: #{plan_list}")
-            raise RuntimeError, "can't find service plan #{plan}, supported plans: #{plan_list}"
+            plan_names = plans.map(&:name).join(", ")
+            @log.error("can't find service plan #{plan}, supported plans: #{plan_names}")
+            raise RuntimeError, "can't find service plan #{plan}, supported plans: #{plan_names}"
           end
           plan = plans.first
           @instance.service_plan = plan