Read and write to /etc/hosts

TL;DR:
- Rename website-blocker to url-blocker
- Add a README.md
- Reads and writes to /etc/hosts

tools/url-blocker/rules.json

@@ -0,0 +1,28 @@
+[
+  {
+    "urls": [
+      "facebook.com",
+      "www.facebook.com",
+      "twitter.com",
+      "www.twitter.com",
+      "youtube.com",
+      "www.youtube.com",
+      "instagram.com",
+      "www.instagram.com"
+    ],
+    "allowed": []
+  },
+  {
+    "urls": [
+      "chat.googleplex.com"
+    ],
+    "allowed": [
+      {
+        "day": "Sunday",
+        "timeslots": [
+          "18:35-18:39"
+        ]
+      }
+    ]
+  }
+]