Enable additional 'Best Practices' ESLint rules

Enable additional rules from the 'Best Practices' list on ESLint's Rules
page.

.eslintrc

@@ -16,17 +16,24 @@
     "curly": "error",
     "dot-notation": "error",
     "eqeqeq": "error",
+    "guard-for-in": "error",
+    "no-caller": "error",
+    "no-case-declarations": "error",
     "no-console": [
       "error",
       { allow: ["warn", "error"] },
     ],
+    "no-extra-bind": "error",
+    "no-lone-blocks": "error",
     "no-self-compare": "error",
     "no-throw-literal": "error",
+    "no-undef-init": "error",
     "no-unused-expressions": "error",
     "no-use-before-define": [
       "error",
       {"functions": false},
     ],
+    "no-useless-concat": "error",
     "semi": "error",
     "strict": ["error", "safe"],
   },