Added surround.vim support for eco files

[mutewinter]

• Adds %, -, and = commands just like ERB
• Does nothing if surround.vim isn't present

[kchmck]

Thanks, but I think this belongs in a separate eco plugin (please create one actually, if you can.) I know I have an eco syntax, but I've decided to deprecate that and only support CoffeeScript by itself or straight embedded.

[AndrewRadev]

@mutewinter, I'm in the same boat regarding a pull request for eco indentation (#85). What do you think about creating a "vim-eco" organization that we and @adidev (see pull request #97) have commit access to?

[mutewinter]

@AndrewRadev sounds good. I may not have much to contribute, however, since filing this issue I've switch to Handlebars :)

[AndrewRadev]

Heh :). Well, I don't know how much I'm going to be using eco in the future, either...

For now, I've created the vim-eco project under my own account, and I'll transfer ownership or create an organization if someone else shows up willing to maintain the code. I've made you a collaborator, so could you push the ftplugin code there?