ci/turris: add Docker container for Turris builds

ci/README.md

@@ -19,3 +19,17 @@ $ docker push registry.labs.nic.cz/knot/knot-resolver/ci/debian-unstable:knot-$K
 $ docker build -t registry.labs.nic.cz/knot/knot-resolver/ci/fedora fedora
 $ docker push registry.labs.nic.cz/knot/knot-resolver/ci/fedora
 ```
+
+* turris
+
+```
+$ docker build -t registry.labs.nic.cz/knot/knot-resolver/ci/turris:omnia turris
+$ docker push registry.labs.nic.cz/knot/knot-resolver/ci/turris:omnia
+```
+
+Alternatively, provide `SDK_REPO` build arg (dir name from https://repo.turris.cz/ )
+
+```
+$ docker build --build-arg SDK_REPO=omnia-nightly -t registry.labs.nic.cz/knot/knot-resolver/ci/turris:omnia-nightly turris
+$ docker push registry.labs.nic.cz/knot/knot-resolver/ci/turris:omnia-nightly
+```

ci/turris/Dockerfile

+FROM debian:stable
+MAINTAINER Knot Resolver <knot-resolver@labs.nic.cz>
+ARG SDK_NAME=OpenWrt-SDK*x86_64
+ARG SDK_REPO=omnia
+
+WORKDIR /tmp
+
+RUN echo "deb http://ftp.debian.org/debian stretch-backports main" >> /etc/apt/sources.list
+
+RUN apt-get update -qq
+RUN apt-get -t stretch-backports install -y git
+RUN apt-get install -y -qqq git-core build-essential libssl-dev libncurses5-dev \
+	unzip gawk zlib1g-dev git subversion mercurial ccache libtinfo-dev libncurses5 \
+	libncurses5-dev wget
+
+RUN wget --quiet "https://repo.turris.cz/$SDK_REPO/" -r -nd -np --accept="$SDK_NAME.tar.bz2" && \
+	tar xjf $SDK_NAME.tar.bz2 && \
+	rm $SDK_NAME.tar.bz2 && \
+	mv $SDK_NAME turris
+
+CMD ["/bin/bash"]