Ask for correct page on patient results/provider paginations

When asking for an initial page for patient results and providers, the client asks for the default 100, but upon subsequent requests, only asks for 10 to keep from having to render a lot simultaneously. Instead of asking for page 11, it asked for page 2.

This patch calculates the correct page to ask for based on the number of records already fetched, and also will stop asking for new records if the server says that there is no "next" page. This also required an upgrade to Thorax, in order to access the response headers.