Updated docker file to use Node (#8704)

Dockerfile

@@ -1,43 +1,16 @@
-FROM ubuntu:trusty
-
-MAINTAINER Sabe Jones <sabe@habitica.com>
-
-# Avoid ERROR: invoke-rc.d: policy-rc.d denied execution of start.
-RUN echo -e '#!/bin/sh\nexit 0' > /usr/sbin/policy-rc.d
-
-# Install prerequisites
-RUN apt-get update
-RUN apt-get install -y \
-    build-essential \
-    curl \
-    git \
-    libfontconfig1 \
-    libfreetype6 \
-    libkrb5-dev \
-    python
-
-# Install NodeJS
-RUN curl -sL https://deb.nodesource.com/setup_6.x | sudo -E bash -
-RUN apt-get install -y nodejs
-
-# Install npm@latest
-RUN curl -sL https://www.npmjs.org/install.sh | sh
-
-# Clean up package management
-RUN apt-get clean
-RUN rm -rf /var/lib/apt/lists/*
+FROM node:boron
 
 # Install global packages
 RUN npm install -g gulp grunt-cli bower mocha
 
 # Clone Habitica repo and install dependencies
-WORKDIR /habitrpg
-RUN git clone https://github.com/HabitRPG/habitica.git /habitrpg
+RUN mkdir -p /usr/src/habitrpg
+WORKDIR /usr/src/habitrpg
+RUN git clone https://github.com/HabitRPG/habitica.git /usr/src/habitrpg
 RUN npm install
 RUN bower install --allow-root
 
-# Create environment config file and build directory
-RUN cp config.json.example config.json
+# Create Build dir
 RUN mkdir -p ./website/build
 
 # Start Habitica