Deceptively simple... I look forward to contributors finding new and exciting test cases.

As suggested:
* This now uses the type checker to see if types match
* Keeps a stackable state for whether the scope is in a constructor (to deal with nested functions)
* Adds a few more corner cases, such as parameter declarations, --/++ expressions, and overlapping classes

The variable scoping logic was bleeding pretty heavily into the walker, so I moved it into its own class. Much clearer separation of concerns now.

Also added a test for IIFEs used to set them.

* Split variableModifications into two Sets
* Corrected computed property names
* Corrected logic around constructor scope depths
* Stopped recursing on nodes with declare keywords
* ++/-- unary expressions only as modifiers

CircleCI is failing.

Also brought in tsutils@2.4.0. That should fix any caching shenanigans.

…er-readonly

# Conflicts:
#	package.json
#	src/language/walker/blockScopeAwareRuleWalker.ts

# Conflicts:
#	src/language/rule/rule.ts
#	src/rules/noReferenceImportRule.ts

# Conflicts:
#	src/rules/completedDocsRule.ts