Remake Sitecore CMS version detector

[AlenPelin]

Currently we rely on sitecore.version.xml to detect Sitecore CMS version, but we need to change this as in certain conditions it cannot be used as the source of truth.

[DmitryKolinchuk]

This functionality is used in the "SIM.Products.ProductHelper.GetProductFullName" method, so it potentially can be considered for implementation.