Add docker file to run tests in an a Ubuntu container

dockerfile

@@ -0,0 +1,15 @@
+FROM node:8
+
+RUN apt-get update \
+    && apt-get install -qq libcairo2-dev libjpeg-dev libpango1.0-dev libgif-dev build-essential g++
+
+RUN mkdir -p /opt/node/js \
+    && cd /opt/node \
+    && npm install canvas color-convert
+
+WORKDIR /opt/node/js
+COPY . /opt/node/js
+
+RUN npm install
+
+CMD ["npm", "run", "test"]

package.json

@@ -27,7 +27,8 @@
   },
   "devDependencies": {
     "chai": "^3.4.1",
-    "jest": "^20.0.4"
+    "jest": "^20.0.4",
+    "jest-cli": "^20.0.4"
   },
   "peerDependencies": {
     "canvas": "^1.6.5"