fluent/fluentd — pull request #490 by sonots (2014-11-25 09:49:08+00:00)
Title: add self.name to configure_proxy error message

For example, writing a plugin mastakenly like:

```
# out_stdout.rb
config_param :foo, :default => true
config_param :foo, :default => false
```

Before: error message shows as:

```
2014-11-25 18:44:14 +0900 [error]: unexpected error error="default value specified twice for foo"
```

After:

```
2014-11-25 18:44:14 +0900 [error]: unexpected error error="Fluent::StdoutOutput: default value specified twice for foo"
```

We can not find which plugin is doing bad easily now.

Just same thing for others.