Use scripts from coursier to handle website (#306)

Referencing https://github.com/coursier/docusaurus-mdoc-scripts as a
submodule in particular

.gitmodules

@@ -0,0 +1,3 @@
+[submodule "scripts/website"]
+	path = scripts/website
+	url = https://github.com/coursier/docusaurus-mdoc-scripts.git

.travis.yml

@@ -9,14 +9,16 @@ cache:
 git:
   depth: false
 before_install:
-  - source scripts/setup-build-tools.sh
+  - source scripts/website/setup-build-tools.sh
 sudo: required
 stages:
   - name: test
   - name: release
     if: (branch = master AND type = push) OR (tag IS present)
   - name: upload-launcher
     if: tag IS present
+  - name: update-versioned-docs
+    if: tag IS present
   - name: update-website
     if: (branch = master AND type = push) OR (tag IS present)
 jobs:
@@ -41,15 +43,24 @@ jobs:
   - scala: 2.12.8
     jdk: openjdk11
   - name: "Website"
-    script: scripts/update-website.sh
+    script: amm scripts/site.sc --publishLocal true
   - stage: release
     script: sbt ci-release
-  - stage: update-website
-    env: PUSH_WEBSITE=1
-    script: scripts/update-website.sh
   - stage: upload-launcher
     name: "Upload launcher"
     script: scripts/upload-launcher.sh
+  - stage: update-versioned-docs
+    env: WEBSITE_DIR=docs/website VERSIONED_DOCS_REPO=almond-sh/versioned-docs
+    script:
+      - amm scripts/site.sc --publishLocal true --npmInstall true --yarnRunBuild true
+      - scripts/website/versioned-docs.sh --update
+  - stage: update-website
+    env: WEBSITE_DIR=docs/website REPO=almond-sh/almond VERSIONED_DOCS_REPO=almond-sh/versioned-docs
+    name: "Push website"
+    script:
+      - scripts/website/versioned-docs.sh
+      - amm scripts/site.sc --publishLocal true --npmInstall true --yarnRunBuild true --relativize true
+      - scripts/website/push-website.sh
 branches:
   only:
   - master

docs/website/pages/en/versions.js

@@ -0,0 +1,112 @@
+/**
+ * Copyright (c) 2017-present, Facebook, Inc.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+const React = require('react');
+
+const CompLibrary = require('../../core/CompLibrary');
+
+const Container = CompLibrary.Container;
+
+const CWD = process.cwd();
+
+const siteConfig = require(process.cwd() + '/siteConfig.js');
+try {
+  var versions = require(`${CWD}/versions.json`);
+} catch (e) {
+  var versions = [];
+}
+
+function Versions() {
+  const latestVersion = versions[0] || '';
+  const language = '';
+  const repoUrl = `https://github.com/${siteConfig.organizationName}/${
+    siteConfig.projectName
+  }`;
+  return (
+    <div className="docMainWrapper wrapper">
+      <Container className="mainContainer versionsContainer">
+        <div className="post">
+          <header className="postHeader">
+            <h1>{siteConfig.title} Versions</h1>
+          </header>
+          <h3 id="latest">Current version</h3>
+          <table className="versions">
+            <tbody>
+              <tr>
+                <th>{latestVersion}</th>
+                <td>
+                  <a
+                    href={`${siteConfig.baseUrl}docs/intro`}>
+                    Documentation
+                  </a>
+                </td>
+                <td>
+                  <a href={`${repoUrl}/releases/tag/v${latestVersion}`}>
+                    Release Notes
+                  </a>
+                </td>
+              </tr>
+            </tbody>
+          </table>
+          <h3 id="rc">Latest Version</h3>
+          Here you can find the latest documentation and unreleased code.
+          <table className="versions">
+            <tbody>
+              <tr>
+                <th>master</th>
+                <td>
+                  <a
+                    href={`${siteConfig.baseUrl}docs/next/intro`}>
+                    Documentation
+                  </a>
+                </td>
+                <td>
+                  <a href={repoUrl}>Source Code</a>
+                </td>
+              </tr>
+            </tbody>
+          </table>
+          <h3 id="archive">Past Versions</h3>
+          <p>
+            Here you can find documentation for previous versions.
+          </p>
+          <table className="versions">
+            <tbody>
+              {versions.map(
+                version =>
+                  version !== latestVersion && (
+                    <tr key={version}>
+                      <th>{version}</th>
+                      <td>
+                        <a
+                          href={`${siteConfig.baseUrl}docs/${version}/intro`}>
+                          Documentation
+                        </a>
+                      </td>
+                      <td>
+                        <a href={`${repoUrl}/releases/tag/v${version}`}>
+                          Release Notes
+                        </a>
+                      </td>
+                    </tr>
+                  ),
+              )}
+            </tbody>
+          </table>
+          <p>
+            You can find past versions of this project on{' '}
+            <a href={`${repoUrl}/releases`}>GitHub</a>.
+          </p>
+        </div>
+      </Container>
+    </div>
+  );
+}
+
+Versions.title = 'Versions';
+
+module.exports = Versions;