docs: add deprecation notice for node versions 6 and 8 (#916)

docs: add deprecation notice for node versions 6 and 8

.travis.yml

@@ -1,8 +1,8 @@
 language: node_js
 sudo: false
 node_js:
-- 6
-- 8
+- 10
+- 12
 cache:
   npm: false
 before_install:
@@ -28,5 +28,5 @@ deploy:
   skip_cleanup: true
   script: npx semantic-release
   on:
-    node: 8
+    node: 12
     repo: watson-developer-cloud/node-sdk

README.md

@@ -49,8 +49,8 @@ Node.js client library to use the Watson APIs.
 </details>
 
 ## ANNOUNCEMENTS!
-### New Major Version
-The new major version, `v4` has been released. The major new feature in this release is native support for Promises. There are some breaking changes - use the [migration guide](https://github.com/watson-developer-cloud/node-sdk/blob/master/UPGRADE-4.0.md) to navigate any changes that affect your code.
+### Supporting Node versions 10+
+The SDK will no longer be tested with Node versions 6 and 8. Support will be officially dropped in v5.
 
 ### Package Rename
 This package has been moved under the name `ibm-watson`. The package is still available at `watson-developer-cloud`, but that will no longer receive updates. Use `ibm-watson` to stay up to date.

package.json

@@ -86,11 +86,11 @@
     "axios": "^0.18.0",
     "dotenv": "^6.2.0",
     "extend": "~3.0.2",
-    "ibm-cloud-sdk-core": "^0.3.1",
+    "ibm-cloud-sdk-core": "^0.3.3",
     "isstream": "~0.1.2",
     "object.pick": "~1.3.0",
-    "websocket": "^1.0.28",
-    "snyk": "^1.192.4"
+    "snyk": "^1.192.4",
+    "websocket": "^1.0.28"
   },
   "engines": {
     "node": ">=6.0.0"