Add .markdownlint.jsonc file from markdownlint-cli2, update README.md accordingly.

.markdownlint.jsonc

@@ -0,0 +1,18 @@
+{
+  "line-length": {
+    "strict": true,
+    "code_blocks": false
+  },
+  "proper-names": {
+    "code_blocks": false,
+    "names": [
+      "CommonMark",
+      "JavaScript",
+      "Markdown",
+      "markdown-it",
+      "markdownlint",
+      "markdownlint-cli2",
+      "Node.js"
+    ]
+  }
+}

README.md

@@ -25,7 +25,7 @@ issues will be fixed automatically.
 If set to `config`, the `markdownlint-cli2-config` command is run and the
 first element of `globs` should specify a supported configuration file.
 
-For more detail: [command line documentation for `markdownlint-cli2`][command-line].
+For more detail: [documentation for `markdownlint-cli2`][command-line].
 
 ### globs (optional)