Add composer.json

This is similar to #2 but uses the files autoload strategy. I think this is more appropriate. It also ignores the tests and uses a branch alias for 1.0.* for the master branch.

Another way to handle this would be to name this package "ooyala/api" and setup the branch alias to 2.0.x-dev instead so that master would represent 2.0.*.

However, since the repository name has php-v2-sdk in its name I went with the path of naming the actual package "v2-api" and opting to consider the v2 api to be versioned differently.

I'm happy to change this to whatever you'd like to see.