1.0.0-rc (hackney ~> 1.9.0)

[stephenmoloney]

Description:

Work on 1.0.0-rc1

• 1.0rc checklist #12 (done)
• introduce Fastimage.info function with both size and type in one pass #18 (done)
• add tests vs some of the most likely potential error cases #23 (todo)

See changelog for description of more changes.

Pending Enhancements

• Add retries to more of the error clauses... not just after @stream_timeout - eg specifically on error, unexpected streaming error while streaming or after {:hackney_response, _stream_ref, data}
• Handle after {:hackney_response, _stream_ref, data} more elegantly
• More elegant error handling - work already done in another branch, just needs to be transposed.

Issues Encountered:

• Cannot successfully use latest hackney versions 1.10.1, 1.10.0 or 1.11.0 primarily due to issue 447 for both reasons laid out in that issue. Made an attempt to debug it in :hackney itself but didn't succeed. I will make a branch showing a reproducible failing build.
• ssl_closed error apparrantly with all versions but builds still pass.