Transforming Node-style APIs into Fantasy-Land Promises

not sure if an API like this belongs to here or `fantasy-promises` but anyway here is how you can use it:
```
var fs = require("fs");
var p = node.call(fs.readFile,'./myfile.js', 'UTF-8');
p.fork(
     function(d) {console.log(d)},
     function(err) {console.log(err)},
 );
```
I can add tests for this if needed.

 (I also noticed that as per `package.json` `fantasy-sorcery` is not depending on `fantasy-promises` right now. Is that intentional?)