Implement /edcal command

Displays the Editorial Calendar! Still a WIP, but let's see if it
works on Mattermost...

index.js

@@ -31,3 +31,64 @@ app.post("/add", (req, res) => {
   const { a, b } = req.body
   res.send({ result: a + b })
 })
+
+app.get("/articles", (req, res) => {
+  let articles = []
+
+  base('Articles').select({
+    maxRecords: 10,
+    view: "Calendar",
+    fields: [
+      "Title",
+      "Author",
+      "Due Date",
+      "Publish Date",
+      "In charge",
+      "Status",
+    ],
+    filterByFormula: "NOT({Status} = 'Stalled')",
+    sort: [
+      { field: "Publish Date", direction: "desc" },
+      { field: "Status", direction: "asc" },
+    ],
+  }).eachPage(function page(records, fetchNextPage) {
+    records.forEach((record) => {
+      console.log(`Got ${record.get('Title')}`)
+      articles.push({
+        title: record.get("Title"),
+        author: record.get("Author"),
+        due_date: record.get("Due Date"),
+        publish_date: record.get("Publish Date"),
+        in_charge: record.get("In charge"),
+        status: record.get("Status"),
+      })
+    })
+
+    fetchNextPage()
+  }, function done(err) {
+    if (err) {
+      console.error(err)
+      res.send({ status: "error", "error": "An error occurred :("})
+      return
+    }
+
+    if (req.body.command != 'edcal') {
+      articleTable = (articles
+        .reverse()
+        .map(a => `|${a.title}|${a.in_charge.map(u=>u.name).join(',')}|${a.due_date}|${a.publish_date}|${a.status}|`)
+        .join("\n"))
+      res.send({
+        response_type: "in_channel",
+        text: `---
+#### Editorial Calendar
+
+|Title|In charge|Due Date|Publish Date|Status|
+|:----|:--------|:-------|:-----------|:-----|
+${articleTable}
+---`,
+      })
+    } else {
+      res.send({ status: "ok", articles: articles.reverse() })
+    }
+  })
+})