Add allPropertiesRequired and noAdditionalProperties options

[a-lavis]

Adds the allPropertiesRequired and noAdditionalProperties options. Each of these options include a subset of the functionality that strict provides.

Here is how the three options interact, as a truth table:

strict	allPropertiesRequired	noAdditionalProperties	All Properties are Required	Additional Properties are not Permitted
T	*	*	T	T
F	T	T	T	T
F	T	F	T	F
F	F	T	F	T
F	F	F	F	F

These changes are not breaking - strict behaves the same way that it did previously.

[codecov]

Codecov Report

Patch coverage: 100.00% and project coverage change: +0.02 🎉

Comparison is base (f5071e1) 89.98% compared to head (dc25ffd) 90.00%.

❗ Current head dc25ffd differs from pull request most recent head 1b844b9. Consider uploading reports for the commit 1b844b9 to get more accurate results

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #494      +/-   ##
==========================================
+ Coverage   89.98%   90.00%   +0.02%     
==========================================
  Files          76       76              
  Lines        1577     1581       +4     
==========================================
+ Hits         1419     1423       +4     
  Misses        158      158              

Impacted Files	Coverage Δ
lib/json-schema/attributes/properties.rb	100.00% <100.00%> (ø)
lib/json-schema/attributes/properties_v4.rb	100.00% <100.00%> (ø)
lib/json-schema/validator.rb	85.24% <100.00%> (+0.17%)	⬆️

☔ View full report in Codecov by Sentry.
📢 Do you have feedback about the report comment? Let us know in this issue.

[a-lavis]

Rubocop is complaining that test/draft4_test.rb is too long - not sure what the best way to split up the class is. Any ideas?

[ekohl]

I usually don't really care about the RuboCop Metrics, especially when it comes to tests.