fix for cli color rendering issue

Use differ from rspec-support to resolve the issue with special characters when rspec is started with color option:

``` ruby
  22) plsql-spec run specified files should report one file examples
     Failure/Error: @stdout.should =~ /1 example/
       expected: /1 example/
            got: "\e[33mRunning specs from spec/test_spec.rb\e[0m\n\n\e[31mFailing tests!\e[0m\n" (using =~)
       Diff:
       @@ -1,2 +1,4 @@
       -/1 example/
       +Running specs from spec/test_spec.rb
       +
       +Failing tests!
```