feature: Role based authorization

[adrianthedev]

This should allow the users to conditionally authorize other users to see and interact with content.

[codecov]

Codecov Report

Merging #74 into master will increase coverage by 1.04%.
The diff coverage is 94.25%.

@@            Coverage Diff             @@
##           master      #74      +/-   ##
==========================================
+ Coverage   96.03%   97.07%   +1.04%     
==========================================
  Files          87      117      +30     
  Lines        1890     3075    +1185     
==========================================
+ Hits         1815     2985    +1170     
- Misses         75       90      +15     

Impacted Files	Coverage Δ
lib/avo/app/tools_manager.rb	50.00% <50.00%> (ø)
spec/dummy/app/avo/filters/published_filter.rb	66.66% <66.66%> (ø)
lib/avo/app/action.rb	80.00% <80.00%> (ø)
lib/avo/engine.rb	85.71% <85.71%> (ø)
lib/avo/app/fields/boolean_field.rb	93.75% <87.50%> (ø)
lib/avo/app/app.rb	88.88% <88.88%> (ø)
lib/avo/app/fields/key_value_field.rb	90.90% <90.90%> (ø)
.../avo/app/fields/field_extensions/has_field_name.rb	91.66% <91.66%> (ø)
...lds/field_extensions/visible_in_different_views.rb	92.59% <92.59%> (ø)
lib/avo/app/resource_fields.rb	92.85% <92.85%> (ø)
... and 145 more

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 82fefb2...c1a849e. Read the comment docs.