* Add is_engine_available_to_download API call
* Fix issue with worker never throwing error if engine is not found
* Add API call to get most recent engine version
* Fix some minor import issues
* Fix web urls
* Fix default server log level
* Add progress bar for project download worker_factory downloads missing engine versions
* Better error handling when invalid version is given
* Add timeouts to engine downloaders
* Added system_safe_path to convert paths to Windows
* Fix issue where engines would not be reported unless a system engine was installed
* Platform independent searching for binaries in engine directory
* Add missing package to requirements.txt
* Better error handling for ffmpeg.get_all_formats()
* Add system_safe_path to more locations in api_server.py
* Fix naming issue with Blender on macos
* Fix path lookups and add engine_path to workers
* Report installed renderers in status
* Remove files included by accident
* Add get_detected_gpus() and supported_render_engines() to Blender class
* Parse help args for Blender
* Return dict instead of list
* Parse args for FFMPEG
* Add API to get renderer args
* Only return available renderers
* Parse help args for Blender
* Return dict instead of list
* Parse args for FFMPEG
* Rebase off master
* Rebase
* Change methods from class methods to instance methods
* FFMPEG format fetching
* Add ffmpeg_downloader.py
* Move shared download logic to downloader_core.py
* Added Windows support and some misc cleanup
* Fix issue with copying contents of .dmg files
* Add FFMPEGDownloader to engine_manager.py
* Add blender_downloader.py
* Add engine_manager.py
* Add additional methods to engine_manager.py
* Refactor file layout to make engines on par with workers
* Add system platform info to status response
* Default to using system platform / cpu if none are provided
* Add API to download an engine and some general cleanup
* Add method to delete downloaded engine
* Add API calls to download engines and delete downloads
* Misc fixes
