Configure simplecov to ignore spec folder

Reduce noise in code coverage output.  All spec files are run 100% in
the test suite.  This lowers the overall code coverage number...sorry :D

Author: eric-hu

spec/spec_helper.rb

@@ -1,7 +1,9 @@
 # SimpleCov is ..rcov for 1.9+
 # https://github.com/colszowka/simplecov
 require 'simplecov'
-SimpleCov.start
+SimpleCov.start do
+  add_filter "/spec/"
+end
 
 # This file is copied to spec/ when you run 'rails generate rspec:install'
 ENV["RAILS_ENV"] ||= 'test'