Integrate into upstream

[mhutch]

Hi!

Would you be willing to integrate this into the upstream mono/t4 repo? I've developed similar functionality and before I publish I'd love to integrate them rather than competing.

https://github.com/mono/t4/tree/build-targets/Mono.TextTemplating.Build

[mhutch]

@jgiannuzzi oops, i just realized you might not have not had a notification without an explicit @-mention

[mhutch]

FYI - in absence of any response, I'm going to move forward with releasing Mono.TextTemplating.Build as-is.