Indented fanced blocks

• Detect indented fenced code blocks in gfm;
• Automatically indent/dedent block when sync changes between buffers;

Markdown list goes here:

- this item has fenced code block

    ```sh
    echo hi
    ```

Support bitbucket format of fenced blocks

This release adds support of bitbucket fenced code blocks in markdown (#2).

```
#!python
def echo():
    pass
```

Fenced block configuration

Add support of custom fenced block per filetype, and allow to refine existing rules via vimrc.

Shorten repository name

Use more short and fancy name for repository.

Proof of Concept

Fenced code blocks as it should be.