upgrade node requirements, bump package up

.travis.yml

@@ -1,7 +1,8 @@
 language: node_js
 node_js:
-   - "0.10"
    - "6"
+   - "7"
+   - "8"
 env:
   - CXX=g++-4.8
 addons:

package.json

@@ -1,7 +1,7 @@
 {
   "name": "emailjs",
   "description": "send text/html emails and attachments (files, streams and strings) from node.js to any smtp server",
-  "version": "1.0.12",
+  "version": "2.0",
   "author": "eleith",
   "contributors": [
     "izuzak",
@@ -30,7 +30,7 @@
     "iconv": "2.2.1"
   },
   "engine": [
-    "node >= 0.10"
+    "node >= 6"
   ],
   "main": "email.js",
   "scripts": {