Updates to @actions/artifact package (#367)

* GZip implementation

* Optimizations and cleanup

* Update tests

* More test updates

* Update packages/artifact/src/internal-utils.ts

Co-Authored-By: Josh Gross <joshmgross@github.com>

* Clarification around Upload Paths

* Refactor to make http clients classes

* GZip fixes

* Documentation around compression

* More detailed status information during large uploads

* Pretty format

* Percentage updates without rounding

* Fix edge cases with formatting numbers

* Update packages/artifact/src/internal-utils.ts

Co-Authored-By: Josh Gross <joshmgross@github.com>

* Cleanup

* Small reorg with status reporter

* PR Feedback

* Cleanup + Simplification

* Test Cleanup

* Mock updates

* More cleanup

* Format fixes

* Overhaul to the http-manager

* Fix tests

* Promisify stats

* Documentation around implementation

* Improvements to documentation

* PR Feedback

* Remove Downloading multiple artifacts concurrently

Co-authored-by: Josh Gross <joshmgross@github.com>

packages/artifact/src/artifact-client.ts

@@ -1,5 +1,16 @@
-import {ArtifactClient, DefaultArtifactClient} from './internal-artifact-client'
-export {ArtifactClient}
+import {UploadOptions} from './internal/upload-options'
+import {UploadResponse} from './internal/upload-response'
+import {DownloadOptions} from './internal/download-options'
+import {DownloadResponse} from './internal/download-response'
+import {ArtifactClient, DefaultArtifactClient} from './internal/artifact-client'
+
+export {
+  ArtifactClient,
+  UploadResponse,
+  UploadOptions,
+  DownloadResponse,
+  DownloadOptions
+}
 
 /**
  * Constructs an ArtifactClient