tools: enforce function name matching in linter

ESLint has a `func-name-matching` rule that requires that function names
match the variable or property to which they are being assigned.

The code base currently has 100% compliance with this rule.

Enable the rule to keep it that way.

PR-URL: https://github.com/nodejs/node/pull/9408
Reviewed-By: Roman Reiss <me@silverwind.io>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Michaël Zasso <targos@protonmail.com>
Reviewed-By: Gibson Fahnestock <gibfahn@gmail.com>
Reviewed-By: Teddy Katz <teddy.katz@gmail.com>
Reviewed-By: Prince John Wesley <princejohnwesley@gmail.com>

.eslintrc

@@ -82,6 +82,7 @@ rules:
   computed-property-spacing: 2
   eol-last: 2
   func-call-spacing: 2
+  func-name-matching: 2
   indent: [2, 2, {SwitchCase: 1, MemberExpression: 1}]
   key-spacing: [2, {mode: minimum}]
   keyword-spacing: 2