Docker: Rust: Make sure cargo is installed

Author: jtimon

Dockerfile

@@ -75,6 +75,13 @@ RUN cd /tmp \
 
 ENV GOROOT=/usr/local/go
 
+# Install cargo
+RUN cd /root \
+    && curl -s -L -O https://static.rust-lang.org/rustup.sh \
+    && bash ./rustup.sh -y --verbose
+ENV PATH="/root/.cargo/bin:${PATH}"
+RUN cargo --help
+
 # lightning-integration
 RUN git clone https://github.com/cdecker/lightning-integration.git /root/lightning-integration \
   && ln -sf /usr/bin/python3 /usr/bin/python \