Bumped the min deployment target to iOS 9+, Xcode to Xcode 11

[dreampiggy]

See more: SDWebImage/SDWebImage#3130

[codecov]

Codecov Report

Merging #9 (4a70960) into master (b281c8a) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master       #9   +/-   ##
=======================================
  Coverage   58.92%   58.92%           
=======================================
  Files           7        7           
  Lines         577      577           
=======================================
  Hits          340      340           
  Misses        237      237           

Flag	Coverage Δ
iOS	58.92% <ø> (ø)

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