[DEVEXP 391] Add source info to build, buildConfig and eval a new build ...

@bparees @ironcladlou @pmorie @csrwng Please review
yeah, absolutely agree that's a big challenge we need to tackle.  We have a lot of touch points that need reliable versioning (api, builder images, applications themselves, just for starters).  Just want to make sure we don't put barriers to progress in place prematurely either.  I'm particularly sensitive to it as the primary maintainer of the sample.