It's a good question.
Yes, SnapDrive has reached End-of-Availability and will be end-of-support soon. SnapDrive is/was tightly integrated with Microsoft Technologies (File-system/MSCS), and therefore it is/was simple to create shared LUNs for MS clustering purposes (such as creating igroup, marking it as 'shared', formating, extending etc etc all done automatically ) which otherwise requires manual steps followed in order. However, if the steps are followed properly then you can acheive the same result as you do with SnapDrive. Here are couple of articles on that :
How to create an MSCS Cluster with shared disk resources without using SnapDrive:
How to set up MSCS with ISCSI Microsoft software initiator without using SnapDrive:
Coming to your query : I guess, you can script the creation of vol,lun,igroup,extending lun etc using PowerShell but rest (I am afraid) will be same as the steps mentioned in the article.
I think PowerShell geeks from NetApp can further highlight or correct me on this.
NetApp PowerShell Toolkit