Implement gzip compression for cad artifacts

The stls from CadQuery and OpenSCAD are not compressed and so we're
throwing away bandwidth and taking a performance hit by not gziping.

Gzip for s3 basically needs to be gziped before upload and than have

'content-type'      :  'text/stl'
'content-encoding'  :  'gzip'
set.

https://stackoverflow.com/questions/8080824/how-to-serve-gzipped-assets-from-amazon-s3

The obvious part that needs to change is putObject in
app/api/src/docker/common/utils.js but there might be a few more
nuances.

resolves #391

app/api/src/docker/openscad/runScad.js

@@ -1,6 +1,8 @@
 const { makeFile, runCommand } = require('../common/utils')
 const { nanoid } = require('nanoid')
 
+const OPENSCAD_COMMON = `xvfb-run --auto-servernum --server-args "-screen 0 1024x768x24" openscad`
+
 /** Removes our generated/hash filename with just "main.scad", so that it's a nice message in the IDE */
 const cleanOpenScadError = (error) =>
   error.replace(/["|']\/tmp\/.+\/main.scad["|']/g, "'main.scad'")
@@ -21,7 +23,15 @@ module.exports.runScad = async ({
   const { x: px, y: py, z: pz } = position
   const cameraArg = `--camera=${px},${py},${pz},${rx},${ry},${rz},${dist}`
   const fullPath = `/tmp/${tempFile}/output.png`
-  const command = `xvfb-run --auto-servernum --server-args "-screen 0 1024x768x24" openscad -o ${fullPath} ${cameraArg} --imgsize=${x},${y} --colorscheme CadHub /tmp/${tempFile}/main.scad`
+  const command = [
+    OPENSCAD_COMMON,
+    `-o ${fullPath}`,
+    cameraArg,
+    `--imgsize=${x},${y}`,
+    `--colorscheme CadHub`,
+    `/tmp/${tempFile}/main.scad`,
+    `&& gzip ${fullPath}`,
+  ].join(' ')
   console.log('command', command)
 
   try {
@@ -36,12 +46,17 @@ module.exports.runScad = async ({
 module.exports.stlExport = async ({ file } = {}) => {
   const tempFile = await makeFile(file, '.scad', nanoid)
   const fullPath = `/tmp/${tempFile}/output.stl`
+  const command = [
+    OPENSCAD_COMMON,
+    `--export-format=binstl`,
+    `-o ${fullPath}`,
+    `/tmp/${tempFile}/main.scad`,
+    `&& gzip ${fullPath}`,
+  ].join(' ')
 
   try {
-    const consoleMessage = await runCommand(
-      `xvfb-run --auto-servernum --server-args "-screen 0 1024x768x24" openscad -o ${fullPath} /tmp/${tempFile}/main.scad`,
-      60000 // lambda will time out before this, we might need to look at background jobs if we do git integration stl generation
-    )
+    // lambda will time out before this, we might need to look at background jobs if we do git integration stl generation
+    const consoleMessage = await runCommand(command, 60000)
     return { consoleMessage, fullPath }
   } catch (error) {
     return { error, fullPath }