Add tests

[yakky]

Description

Add comprehensive test suite

References

Fix #2

Checklist

• I have read the contribution guide
• Code lint checked via inv lint
• changes file included (see docs)
• Usage documentation added in case of new features
• Tests added

[codecov]

Codecov Report

Merging #10 (8a2b3da) into master (c69ecbe) will increase coverage by 96.93%.
The diff coverage is 95.23%.

@@             Coverage Diff             @@
##           master      #10       +/-   ##
===========================================
+ Coverage    0.00%   96.93%   +96.93%     
===========================================
  Files           6        7        +1     
  Lines         155      163        +8     
  Branches       23       26        +3     
===========================================
+ Hits            0      158      +158     
+ Misses        155        2      -153     
- Partials        0        3        +3     

Flag	Coverage Δ
unittests	96.93% <95.23%> (+96.93%)	⬆️

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Impacted Files	Coverage Δ
app_enabler/__main__.py	0.00% <ø> (ø)
app_enabler/patcher.py	93.84% <90.00%> (+93.84%)	⬆️
app_enabler/cli.py	100.00% <100.00%> (+100.00%)	⬆️
app_enabler/django.py	100.00% <100.00%> (+100.00%)	⬆️
app_enabler/errors.py	100.00% <100.00%> (ø)
app_enabler/install.py	100.00% <100.00%> (+100.00%)	⬆️
... and 2 more

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[coveralls]

Pull Request Test Coverage Report for Build 433410029

• 21 of 21 (100.0%) changed or added relevant lines in 5 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+96.7%) to 97.706%

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Totals
Change from base Build 404164059:	96.7%
Covered Lines:	162
Relevant Lines:	164

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💛 - Coveralls