Add bash to sdk container image (#28)

Author: schmidma

naosdk/Containerfile

@@ -13,7 +13,7 @@ ARG version
 COPY --chmod=744 HULKs-OS-*.sh /opt/
 RUN /opt/HULKs-OS-$(uname -m)-toolchain-${version}.sh -d /naosdk
 
-FROM busybox
+FROM alpine
+RUN apk add --no-cache bash
 COPY --from=build /naosdk /naosdk
-RUN ln -s /naosdk/sysroots/$(uname -m)-naosdk-linux/bin/bash /bin/bash
 RUN echo . /naosdk/environment-setup-corei7-64-aldebaran-linux >> /root/.bashrc