Bumped swift tools version. Bumped Perfect-Net version

Removed direct crypto dep

Fixed warnings

factored out reliance on PerfectHTTP*

Only retry once after being throttled

Fixed Linux compilation with Dispatch

Merge pull request #7 from PerfectlySoft/curses

Curses

Merge pull request #6 from PerfectlySoft/ifatfirst

Ping APNS server before reusing existing connection. Open new connect…

Bumped to 3.0

Merge pull request #5 from PerfectlySoft/keep_error_msg

No longer discard helpful error message