Retry policy support for v2

[gavin-aguiar]

Added support for retry policy for V2 programming model.

PR includes adding a new SettingApi which is similar to TriggerApi and BindingsApi. Function Name and Retry decorators will be part of the SettingsApi

[codecov[bot]]

Codecov Report

Merging #182 (72d353f) into dev (5ef605e) will increase coverage by 0.20%. The diff coverage is 100.00%.

@@            Coverage Diff             @@
##              dev     #182      +/-   ##
==========================================
+ Coverage   90.50%   90.70%   +0.20%     
==========================================
  Files         106       55      -51     
  Lines        6256     3185    -3071     
  Branches     1097      822     -275     
==========================================
- Hits         5662     2889    -2773     
+ Misses        439      219     -220     
+ Partials      155       77      -78     

Flag	Coverage Δ
unittests	90.67% <100.00%> (+0.18%)	:arrow_up:

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
azure/functions/decorators/__init__.py	100.00% <ø> (ø)
azure/functions/__init__.py	100.00% <100.00%> (ø)
azure/functions/decorators/core.py	98.86% <100.00%> (+0.23%)	:arrow_up:
azure/functions/decorators/function_app.py	99.30% <100.00%> (+0.03%)	:arrow_up:
azure/functions/decorators/function_name.py	100.00% <100.00%> (ø)
azure/functions/decorators/retry_policy.py	100.00% <100.00%> (ø)

... and 53 files with indirect coverage changes