Split add job helper (#45)

* Fix issue with engine not being available to download

* Add version caches to ffmpeg downloader

* Remove some test parameters

* "releases" should be "release" in linux ffmpeg url

* CPU was incorrectly reported as OS

* Fix naming structure for FFMPEG downloads for linux

* More linux ffmpeg work

* Improved error handling

* WIP

* Consolidate platform reporting to not use platform directly

* Fix missing folder name

* Fix project output naming

* Undo config.yaml commit

* Add is_engine_available API call

* Fix issue where subjobs would not find servers

src/api/server_proxy.py

@@ -116,6 +116,9 @@ class RenderServerProxy:
     def get_status(self):
         return self.request_data('status')
 
+    def is_engine_available(self, engine_name):
+        return self.request_data(f'{engine_name}/is_available')
+
     def notify_parent_of_status_change(self, parent_id, subjob):
         return requests.post(f'http://{self.hostname}:{self.port}/api/job/{parent_id}/notify_parent_of_status_change',
                              json=subjob.json())