Fix listing devices and calls to next page

It looks like the listing devices methods were using options/params and method names inconsistently (undefined method exception) and a bug in next page was causing 404s for APIDs.  I also simplified the parameter parsing from the query string using Rack Utils method for this.

- Simplify parsing the parameters from the query string in the next page
- Fix next page for list apids (api matched apids)
- Fix all the calls to device listing (params instead of options)
- Remove parameters to next page - it prevented multiple calls to next page from working
- Update documentation for device listing methods to clarify how you get device tokens from the response