Add org2blog and quickrun support in contrib layer.

[hujianxin]

• org2blog is an extentions for wordpress. Key binding to SPC a o
• quickrun.el is a extension to execute editing buffer. Keybinding to SPC a q

[syl20bnr]

Thank you !

Ouch this PR has a lot of stuff.
From what I can tell there is:

• org2blog
• quickrun
• some Chinese integration via LaTeX

Can you make one distinct PR per topic ? You can create a branch per PR to make them distinct.

I have some comment though:

• The org Chinese integration could start a new chinese layer.
• I'm not sure we need quickrun in spacemacs, each layer are pretty well integrated and respect some conventions so quickrun is not really useful
• org2blog layer seems cool, prefer a logo of wordpress instead of a screenshot.

[hujianxin]

@syl20bnr Hi, I created a new branch called org2blog, and make a PR. As for chinese layer, I need some time to do it .