Add GoCV to dev environment

Dockerfile

@@ -4,6 +4,7 @@ LABEL maintainer="himself@stevenpolley.net"
 # Update packages
 RUN sudo apt update && \
     sudo apt upgrade -y && \
+    sudo apt install pkg-config make -y && \
     sudo apt clean autoclean && \
     sudo apt autoremove -y
 
@@ -14,6 +15,12 @@ RUN curl -L -O https://dl.google.com/go/go1.15.2.linux-amd64.tar.gz && \
     sudo mv go /usr/local && \
     rm -f go1.15.2.linux-amd64.tar.gz
 
+# Install OpenCV (via GoCV bindings)
+RUN go get -u -d gocv.io/x/gocv && \
+    cd /home/coder/go/src/gocv.io/x/gocv && \
+    make install && \
+    make clean
+
 # Install Hugo
 RUN curl -L -O https://github.com/gohugoio/hugo/releases/download/v0.75.1/hugo_0.75.1_Linux-64bit.tar.gz && \
     tar xvfz hugo_0.75.1_Linux-64bit.tar.gz && \