Encode a video to mp4 with optional cropping using FFMPEG, triggered by Azure Blob storage
##Prerequisites
- dotnetcore2.0 SDK https://www.microsoft.com/net/download/windows
- Azure Storage Emaulator https://docs.microsoft.com/en-us/azure/storage/common/storage-use-emulator
- Visual Studio 2017
- Azure Functions and Web Jobs Tools extension for Visual Studio