[New] node v8.8+ supports http2

Fixes #139.

Author: ljharb

lib/core.json

@@ -12,12 +12,13 @@
     "dns": true,
     "domain": true,
     "events": true,
-    "freelist": "< 6.0.0",
+    "freelist": "< 6",
     "fs": true,
     "http": true,
+    "http2": ">= 8.8",
     "https": true,
     "_http_server": ">= 0.11",
-    "_linklist": "< 8.0.0",
+    "_linklist": "< 8",
     "module": true,
     "net": true,
     "os": true,