Extended Octopress CLI with ink info command.

I've made some changes to this since my original write up in #5. After using it, it makes more sense to use asset type flags hide other asset types, defaulting to all instead of none. For example:

```bash
$ octopress ink info theme
```
looks like this:

![screenshot of iterm](https://f.cloud.github.com/assets/12732/2227548/28fc9eec-9ac5-11e3-99eb-3b03f402a63e.png)

```bash
$ octopress ink info theme
```

looks like this:

![screenshot of iterm](https://f.cloud.github.com/assets/12732/2227557/61048bec-9ac5-11e3-8b78-841014647061.png)

Here's a look at what you get if you just run `octopress ink info`.

![screenshot of iterm](https://f.cloud.github.com/assets/12732/2227561/8d513970-9ac5-11e3-91d7-702d9b252324.png)