Update package.json with stuff needed for npm

Resolves #220

package.json

@@ -1,7 +1,29 @@
 {
   "name": "realm",
-  "version": "0.0.1",
-  "private": true,
+  "description": "Realm is a mobile database: an alternative to SQLite & key-value stores",
+  "version": "0.1.0",
+  "license": "Apache-2.0",
+  "homepage": "https://realm.io",
+  "keywords": [
+    "realm",
+    "database",
+    "db",
+    "react",
+    "react-native",
+    "sqlite"
+  ],
+  "author": {
+    "name": "Realm",
+    "email": "help@realm.io",
+    "url": "https://realm.io"
+  },
+  "repository": {
+    "type": "git",
+    "url": "https://github.com/realm/realm-js.git"
+  },
+  "bugs": {
+    "url": "https://github.com/realm/realm-js/issues"
+  },
   "main": "lib/index.js",
   "files": [
     "android",
@@ -21,5 +43,8 @@
   },
   "devDependencies": {
     "jsdoc": "^3.4.0"
+  },
+  "engines": {
+    "node": ">=4"
   }
 }