fixes #13, allows parameters after docker run command

Dockerfile

@@ -13,6 +13,6 @@ RUN go get ./
 # build & install server
 RUN go install . 
 
-ENTRYPOINT /go/bin/app --port 8080  
+ENTRYPOINT ["/go/bin/app", "--port", "8080"]  
 
 EXPOSE 8080