Add support for generating a StackId when rendering a template

[dhutchison]

Adds in a default value for the StackId property and a function to generate a StackId if it is not already set

Fixes #384

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 94.82%. Comparing base (f1b9d72) to head (5d8fae1).
Report is 91 commits behind head on develop.

Additional details and impacted files

@@             Coverage Diff             @@
##           develop     #397      +/-   ##
===========================================
- Coverage    95.00%   94.82%   -0.18%     
===========================================
  Files           11       12       +1     
  Lines          760      850      +90     
  Branches       155      160       +5     
===========================================
+ Hits           722      806      +84     
- Misses          21       24       +3     
- Partials        17       20       +3     

Flag	Coverage Δ
unit	94.82% <100.00%> (-0.18%)	⬇️

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

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.