I know that bitnami has moved all his images to the Azure Marketplace, but there was others VM on vmdepot. Now there is no simple way to share virtual machines on Azure.
As you mentioned, Microsoft Azure decide to removed their old VM Depot Marketplace and all the Bitnami Images have been moved to their new Marketplace:
https://azure.microsoft.com/en-us/marketplace/.
You can create your a virtual machine image for the Azure Marketplace and publish it following the guide below:
https://azure.microsoft.com/en-us/documentation/articles/marketplace-publishing-vm-image-creation/