Replace custom python connector with ncat (#42)

* Replace custom made daemon with nmap-ncat

* Use stderr to log ncat output

* Refresh the branch

connector/Dockerfile

@@ -0,0 +1,9 @@
+FROM alpine:edge
+
+RUN apk add --no-cache coreutils nmap-ncat
+
+EXPOSE 2560/tcp
+
+SHELL ["/bin/ash", "-c"]
+CMD stty -F /dev/arduino -echo 115200 && \
+    ncat -n -k -l 2560 </dev/arduino >/dev/arduino