Travis CI (#155)

* try using travis

* comments

* docker

* fix

* fix

Dockerfile

@@ -0,0 +1,16 @@
+# For travis
+FROM buildpack-deps:xenial
+SHELL ["/bin/bash", "-c"]
+ENV DEBIAN_FRONTEND=noninteractive LANG=C.UTF-8
+RUN mkdir -p /root/emsdk/
+COPY . /root/emsdk/
+
+RUN cd /root/ \
+ && apt-get update \
+ && apt-get install -y python cmake build-essential openjdk-9-jre-headless \
+ && /root/emsdk/emsdk install latest \
+ && /root/emsdk/emsdk activate latest \
+ && source /root/emsdk/emsdk_env.sh --build=Release \
+ && echo "int main() {}" > hello_world.cpp \
+ && emcc hello_world.cpp
+