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/common/utils.js

@@ -117,7 +117,7 @@ async function storeAssetAndReturnUrl({
     let buffer
 
     try {
-      buffer = await readFile(fullPath)
+      buffer = await readFile(`${fullPath}.gz`)
     } catch (e) {
       console.log('read file error', e)
       const response = {
@@ -134,6 +134,8 @@ async function storeAssetAndReturnUrl({
         Key: key,
         Body: buffer,
         CacheControl: `max-age=${FiveDays}`, // browser caching to stop downloads of the same part
+        ContentType: 'text/stl',
+        ContentEncoding: 'gzip',
         Metadata: putConsoleMessageInMetadata(consoleMessage),
       })
       .promise()