Moffee

What's Changed
* add encoding="utf8" to resolve UnicodeDecodeError: 'gbk' codec can't… by allenwoods in https://github.com/BMPixel/moffee/pull/4 Now moffee works correctly with Chinese characters in Windows environment.

New Contributors
* allenwoods made their first contribution in https://github.com/BMPixel/moffee/pull/4

**Full Changelog**: https://github.com/BMPixel/moffee/compare/v0.2.6...v0.2.7

**Full Changelog**: https://github.com/BMPixel/moffee/compare/v0.2.5...v0.2.6

- Improve auto-sizing function to be more consistent and optimal
- Make beam theme title look better
- Support `aspect_ratio` option in front matter.

Add--version cli option

Introduce 4 bultin themes:

- beam: Professional theme inspired from beamer
- robo: A simple and modern theme
- blue: A theme with dark blue background
- gaia: Theme with paper and handwritting style

Add basic support for themes

First stable version. Features:

- Auto pagination and styling
- Extended markdown support
- Layout dividers
- export to PDF and live reload mode