switch Dockerfile base from node to golang (for Hugo modules), update deps

[skip ci]

Dockerfile

@@ -3,34 +3,44 @@
 #     docker run -v $(pwd):/src -p 1337:1337 jarv.is
 # ...then open http://localhost:1337 for the live-refresh server.
 #
-# Based on: https://github.com/jakejarvis/hugo-build-action/blob/master/Dockerfile
+# Based on: https://hub.docker.com/r/jakejarvis/hugo-extended
 
-FROM node:lts-alpine
+# Hugo doesn't require Go to run, *except* if you're using Hugo Modules. It's
+# much easier to install Node on the Go base image than vice-versa.
+FROM golang:1.14-alpine
 
 ENV HUGO_VERSION 0.68.3
 # remove/comment the following line completely to build with vanilla Hugo:
 ENV HUGO_EXTENDED 1
 
+LABEL maintainer="Jake Jarvis <jake@jarv.is>"
+LABEL homepage="https://jarv.is/"
+LABEL repository="https://github.com/jakejarvis/jarv.is"
+
 # only install libc6-compat & libstdc++ if we're building extended Hugo
 # https://gitlab.com/yaegashi/hugo/commit/22f0d5cbd6114210ba7835468facbdee60609aa2
 RUN apk update && \
     apk add --no-cache \
       ca-certificates \
       git \
+      nodejs \
+      npm \
+      yarn \
       python3 \
+      py3-pip \
       ruby \
       ${HUGO_EXTENDED:+libc6-compat libstdc++} && \
     update-ca-certificates && \
-    npm install --global postcss-cli autoprefixer && \
-    pip3 install --upgrade pip Pygments==2.* && \
+    npm install --global postcss-cli autoprefixer @babel/core @babel/cli && \
+    pip3 install --upgrade Pygments==2.* && \
     gem install asciidoctor && \
     wget https://github.com/gohugoio/hugo/releases/download/v${HUGO_VERSION}/hugo_${HUGO_EXTENDED:+extended_}${HUGO_VERSION}_Linux-64bit.tar.gz && \
     wget https://github.com/gohugoio/hugo/releases/download/v${HUGO_VERSION}/hugo_${HUGO_VERSION}_checksums.txt && \
     grep hugo_${HUGO_EXTENDED:+extended_}${HUGO_VERSION}_Linux-64bit.tar.gz hugo_${HUGO_VERSION}_checksums.txt | sha256sum -c && \
     tar xf hugo_${HUGO_EXTENDED:+extended_}${HUGO_VERSION}_Linux-64bit.tar.gz && \
-    mv ./hugo /usr/bin && \
-    chmod +x /usr/bin/hugo && \
-    rm -rf hugo_*
+    mv hugo /usr/local/bin/ && \
+    chmod +x /usr/local/bin/hugo && \
+    rm -rf hugo_* LICENSE README.md
 
 # verify everything's OK
 RUN hugo env && \