Fix spell check (needed if such java is included) and added other codeblocks

### Fix spell check

[syntax/java.vim](https://code.google.com/p/vim/source/browse/runtime/syntax/java.vim#161)                                                                has a line `syntax spell default` and it disables spell check at toplevel.

To enable spell check at toplevel, add `syntax spell toplevel` at the endof `enable_quote_syntax()`

### Add other codeblocks than triple backticks

Following codeblocks are included:

* [Fenced codeblock (waves) at PHP Markdown Extra](https://michelf.ca/projects/php-markdown/extra/#fenced-code-blocks)
* [Liquid highlight tag](http://jekyllrb.com/docs/templates/): Related to #2
* [Codeblock - Octopress](http://octopress.org/docs/plugins/codeblock/)

In addition, users can use `g:markdown_quote_syntax_codeblocks`
to add other codeblocks as written in README.