Introduce semantic-release

BREAKING CHANGE: Every call to marked is isolated now. This makes sure that options from the first call won't influence options from the second call. If you've configured the markdown-loader with two different options, you might observe different behavior now. We also removed Node v8 and Node v10 support and support for older webpack versions. Webpack 5 is required now.

Author: jhnns

.releaserc.json

@@ -0,0 +1,16 @@
+{
+  "branches": ["main", { "name": "beta", "prerelease": true }],
+  "plugins": [
+    "@semantic-release/commit-analyzer",
+    "@semantic-release/release-notes-generator",
+    "@semantic-release/changelog",
+    [
+      "@semantic-release/git",
+      {
+        "assets": ["CHANGELOG.md"]
+      }
+    ],
+    "@semantic-release/github",
+    "@semantic-release/npm"
+  ]
+}