Update Dockerfile-1.9 and create Dockerfile-1.10

[orthomind]

I've copied the Dockerfile-1.9 and Dockerfile-1.10 files from the decred/dcrd repository. As best I can tell, it appears some of the 'decred-golang-builder' images are build from decred/dcrdocker, while more recent ones are from decred/dcrd (if that's not correct, please let me know).

These images appear to be distinct from dcrd, and used across repos, so I think it makes sense to have them in decred/dcrdocker. My proposal:

1. Merge this PR
2. Update docker hub build process to use images from this repo only (decred-golang-builder-1.9 and decred-golang-builder-1.10 specifically)
3. I'll create a PR to remove these Dockerfiles from decred/dcrd once they're not being used

[dajohi]

Please rebase against master. Also, remove Dockerfile-1.8 since you are adding 1.10.

[orthomind]

@dajohi Done

[dajohi]

Also, please force the specific current latest version for both 1.9 and 1.10.

[orthomind]

Also done.