Announcing The Exchange Server 2019 Sizing Calculator

@sfrndoc - here are my thoughts on those questions: There are also definitive benefits of adding the Calc into the .ISO. What is in the .ISO is officially checked into the build and has the same support / bug fix process behind it as the rest of the product. There were definitely issues in the past where the Calculator would kind of be left alone because it was its own thing that our customers needed to download it from somewhere else, it was not updated regularly etc. On versions of Exchange - we heard this question several times at last year's Microsoft Ignite conference... and actually addressed it in this blog post after Ignite: https://techcommunity.microsoft.com/t5/exchange-team-blog/faqs-from-exchange-and-outlook-booths-at-2019-microsoft-ignite/ba-p/1053448 (see under "Will there be another version of Exchange server on-premises?")