Move to installing from downloaded ISO

[KennethB]

https://github.com/chocolatey/choco/wiki/How-To-Mount-An-Iso-In-Chocolatey-Package

[KennethB]

http://download.microsoft.com/download/8/4/3/843ec655-1b67-46c3-a7a4-10a1159cfa84/vs2015.3.ent_enu.iso

[tsvietOK]

@KennethB Looks like VS2015 installer resources were removed from Microsoft servers. Link in this package, which is used to download VS installer is working, but install fails due to "A setup package is missing or damaged".
https://developercommunity.visualstudio.com/t/Failed-to-install-Visual-Studio-2015-Ent/1407976?space=8&q=damaged&sort=newest
"VS2015 installs are currently impacted. On April 26, 2021, Visual Studio 2015 and older web installer files were removed from the Microsoft Download Center. These products can be installed from ISO images available at https://my.visualstudio.com/downloads."
BTW, here is a link for VS2015 Pro Update 3: http://download.microsoft.com/download/e/b/c/ebc2c43f-3821-4a0b-82b1-d05368af1604/vs2015.3.pro_enu.iso