OmniMarkupPreviewer v3.0.0 Changelog:

**NOTE:** Restarting Sublime Text may required after upgrading.

* Use new flat github style (old style renamed to github-v1).
* Upgrade pygments library to v2.0.2, with more lexers.
* Upgrade `Python-Markdown` package to v2.4.1 final.
* Add `.mmd` file extension support (MultiMarkdown).
* Upgrade jQuery to 2.1.3 (Say good bye to IE8).
* `server_host` setting is now taken into account when launching preview in browser.
