Issue #1889006 by mikeytown2: Add in a save file example to the readme and update readme due to new changes in the API.

Issue #1891676 by mikeytown2: Fix global timeout issues and php timeout issues in background callbacks.

Issue #1874764 by mikeytown2: auto adjust time to first byte timeout if timeout is larger than default.

Issue #1426854 by mikeytown2: If a range request was made, and a 200 was returned, transform it into a 206.

Issue #1426854 by mikeytown2: If a range request was made, and a 200 was returned, transform it into a 206.

Issue #1873954 by mikeytown2: Fix false timeout with async_connect and fix options with array of urls.

Issue #1869002 by mikeytown2: Remove the head_only option. Strict enforcement of the Range header will be a better option.

Issue #1869002 by mikeytown2: Remove the head_only option. Strict enforcement of the Range header will be a better option.

Issue #1869002 by mikeytown2: Allow for only the HTML HEAD to be downloaded when using things like GET.

Issue #1826624 by mikeytown2: Allow background callbacks to be made at a lighter bootstraping level.