This is a follow up to the PR #697 (Issue #550). Currently bin/benchpark show-build dump can be used to output the raw build instructions for an application. However, this only outputs the build logs for the root level application. Instructions for any package dependencies still have to be pieced together manually. More importantly, the build instructions do not output which source repo was used and how it was downloaded. This is often tedious to figure out, especially if an upstreamed spack package.py is being used. It would be nice extend bin/benchpark show-build dump` to support the following:

• Generate build instructions for the application along with all its the package dependencies
• Generate instructions on where to fetch the source repo for the application (and its dependencies), which branch/release/version to use and what patches, if any, to apply
• Dump the entire spack concretizer output
• If possible, dump the spack runtime environment variables used when running the experiment.
• Write out any conflicts (e.g., CUDA version MFEM doesn't work with - which may be listed in Laghos or MFEM package)
• Write out runtime parameters and environment variables that are set