add contributors action

adds GitHub Action to update the list of contributors when a new author pushes a change.

.github/scripts/contributors.js

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+const fs = require('fs')
+const cheerio = require('cheerio');
+const pretty = require('pretty');
+const page = fs.readFileSync('./website/sources/index.html', {encoding: 'utf-8' })
+var contributors = fs.readFileSync('./contributors.txt', {encoding: 'utf-8' }).split('\n')
+const $ = cheerio.load(page)
+var eventJson = JSON.parse(fs.readFileSync(process.env.GITHUB_EVENT_PATH, {encoding: 'utf-8' }));
+
+$('#contributors-list').empty() // remove all names to start clean
+for (let name of contributors) {
+  if (name.length > 0) {
+    for (let commit of eventJson.commits) {
+      // we only look for authors, not commiters, so we automatically ignore "actions-user"
+      if ( !contributors.includes(commit.author.name) ) {
+        contributors.push(commit.author.name)
+      }
+    } 
+    $('#contributors-list').append(`<li>${name}</li>\n`)
+  }
+}
+// write out new contributors.html file
+let newHtml = pretty($.html(), {ocd: true})
+fs.writeFileSync('./website/sources/index.html', newHtml, {encoding: 'utf-8'})
+// write out contributors.txt
+let newTxt = "";
+contributors.map( x => {
+  if (x) {
+    newTxt = newTxt.concat(`${x}\n`)
+  }
+})
+fs.writeFileSync('./contributors.txt', newTxt, {encoding: 'utf-8'})

.github/workflows/add-contributors.yml

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+name: Add contributors
+
+on:
+  push:
+    branches: 
+      - "master"
+      - "main"
+
+jobs:
+  update-contributors:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
+
+    - name: Update text and html files
+      run: |
+        npm install cheerio
+        npm install pretty
+        node ./.github/scripts/contributors.js 
+
+    - uses: stefanzweifel/git-auto-commit-action@v4
+      with:
+        commit_message: update contributors

contributors.txt

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+Alissa M
+Paul Schulz
+Gareth Dixon
+Andrew Kelly