added function to change access tier of blob

[MatthewEai]

Archived blobs are not accessible via other methods in AzStorage or CloudSeis such as csopen, or cp. In order to access these blobs, they must be rehydrated by changing the access tier. I have added a method to AzStorage for rehydrating blobs from the access tier archive to one of Cold, Cool, or Hot.

[codecov]

Codecov Report

❌ Patch coverage is 0% with 35 lines in your changes missing coverage. Please review.
✅ Project coverage is 76.61%. Comparing base (5ab726f) to head (2716b53).
⚠️ Report is 4 commits behind head on master.

Files with missing lines	Patch %	Lines
src/AzStorage.jl	0.00%	35 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master      #88      +/-   ##
==========================================
- Coverage   80.69%   76.61%   -4.09%     
==========================================
  Files           1        1              
  Lines         461      496      +35     
==========================================
+ Hits          372      380       +8     
- Misses         89      116      +27     

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[samtkaplan]

closed in favor of #90.