This sequence is mystifying and should be reduced into something more logical:

1. Pick a bunch of parameters off of the `spec`, and put them onto the `op`. However, the `method` parameter has been translated to `httpMethod`
    * What makes `method` special such that it should be named differently on the `spec` than on the `op`?
2. Then, use `_.extend` after any way, which kind of repeats everything that happened in step 1
    * Also implies the `op` will have both `httpMethod` and `method` ?
3. Then do one more pick out of `spec` to pull in the `responseClass` with a default of `'void'`

Can you figure out if all this is actually necessary, and maybe a better way to do it? Also, look at the difference between `spec` and `op`, and determine if maybe they are just the exact same thing. If so, we should try and normalize that in our representation.