Build.sh

Added a simple build script to run before submitting pull requests.

Spawns an xterm for each dockerfile in the repo and tests to make sure it builds. Accepts arguments. Highly recommend passing --no-cache when verifying builds actually build.
Awesome! As other people start contributing to the codebase, we can modify the script to match their tools via parameters. Example: `./build.sh --server root@127.0.0.1 --cli xterm ...`

But for now this fits my use case :smile: