Update nodejs for Aug/2018 security patches (#82)

Closes #80
diff --git a/core/nodejs6Action/CHANGELOG.md b/core/nodejs6Action/CHANGELOG.md
index 97d75fe..f2a218a 100644
--- a/core/nodejs6Action/CHANGELOG.md
+++ b/core/nodejs6Action/CHANGELOG.md
@@ -19,6 +19,11 @@
 
 # NodeJS 6 OpenWhisk Runtime Container
 
+## 1.11.3
+Change: Update Node.js
+
+Node.js version = [6.14.4](https://nodejs.org/en/blog/release/v6.14.4/)
+
 ## 1.11.2
 Change: Update runtime to allow more environment variables
 
diff --git a/core/nodejs6Action/Dockerfile b/core/nodejs6Action/Dockerfile
index bd55807..8bdf50c 100644
--- a/core/nodejs6Action/Dockerfile
+++ b/core/nodejs6Action/Dockerfile
@@ -18,7 +18,7 @@
 FROM nodejsactionbase
 
 # based on https://github.com/nodejs/docker-node
-ENV NODE_VERSION 6.14.3
+ENV NODE_VERSION 6.14.4
 RUN curl -SLO "https://nodejs.org/dist/v$NODE_VERSION/node-v$NODE_VERSION-linux-x64.tar.gz" \
   && tar -xzf "node-v$NODE_VERSION-linux-x64.tar.gz" -C /usr/local --strip-components=1 \
   && rm "node-v$NODE_VERSION-linux-x64.tar.gz"
diff --git a/core/nodejs8Action/CHANGELOG.md b/core/nodejs8Action/CHANGELOG.md
index 63153e1..2cae9b2 100644
--- a/core/nodejs8Action/CHANGELOG.md
+++ b/core/nodejs8Action/CHANGELOG.md
@@ -19,6 +19,11 @@
 
 # NodeJS 8 OpenWhisk Runtime Container
 
+## 1.8.3
+Change: Update Node.js
+
+Node.js version = [8.11.4](https://nodejs.org/en/blog/release/v8.11.4/)
+
 ## 1.8.2
 Change: Update runtime to allow more environment variables
 
diff --git a/core/nodejs8Action/Dockerfile b/core/nodejs8Action/Dockerfile
index c497a56..20e150a 100644
--- a/core/nodejs8Action/Dockerfile
+++ b/core/nodejs8Action/Dockerfile
@@ -15,7 +15,7 @@
 # limitations under the License.
 #
 
-FROM node:8.11.3
+FROM node:8.11.4
 RUN apt-get update && apt-get install -y \
     imagemagick \
     unzip \