Separate AWS cache options and normalize implementations

[JimBobSquarePants]

Prerequisites

• I have written a descriptive pull-request title
• I have verified that there are no overlapping pull-requests open
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• I have provided test coverage for my change (where applicable)

Description

While the options types share the same properties, it's important to maintain separate options classes to allow further extensibility and simplify json configuration.

[codecov]

Codecov Report

Merging #219 (c480a6f) into master (376c0e6) will increase coverage by 0%.
The diff coverage is 100%.

@@          Coverage Diff          @@
##           master   #219   +/-   ##
=====================================
  Coverage      87%    87%           
=====================================
  Files          70     71    +1     
  Lines        1826   1831    +5     
  Branches      269    269           
=====================================
+ Hits         1589   1594    +5     
  Misses        167    167           
  Partials       70     70           

Flag	Coverage Δ
unittests	87% <100%> (+<1%)	⬆️

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Impacted Files	Coverage Δ
...geSharp.Web.Providers.AWS/AmazonS3ClientFactory.cs	18% <ø> (ø)
....AWS/Providers/AWSS3StorageImageProviderOptions.cs	100% <ø> (ø)
...ders.Azure/Caching/AzureBlobStorageCacheOptions.cs	100% <ø> (ø)
.../Providers/AzureBlobStorageImageProviderOptions.cs	100% <ø> (ø)
...arp.Web.Providers.AWS/Caching/AWSS3StorageCache.cs	87% <100%> (ø)
....Providers.AWS/Caching/AWSS3StorageCacheOptions.cs	100% <100%> (ø)

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