fix gitpod (#658)

.gitpod.dockerfile

@@ -0,0 +1,15 @@
+FROM gitpod/workspace-full
+
+RUN sudo apt-get update \
+    && sudo apt-get install -yq --no-install-recommends \
+        libpng16-16 \
+        libpng-dev \
+        pkg-config \
+        autoconf \
+        libtool \
+        build-essential \
+        nasm \
+        libx11-dev \
+        libxkbfile-dev \
+    && sudo rm -rf /var/lib/apt/lists/*
+

.gitpod.yml

@@ -1,7 +1,11 @@
+image:
+  file: .gitpod.dockerfile
+
 tasks:
     - before: nvm install 10 && nvm use 10
       init: npm install
-      command: npm run start
+      command: npm run start-server
+
 ports:
     - port: 8080
       onOpen: open-preview

README.md

@@ -46,5 +46,5 @@ Use a browser based dev environment
 Or clone locally and run
 ```
 npm install
-npm run start
+npm run start-server
 ```