Greater control over install process - config.json

[jsta]

Description

https://github.com/CrayLabs/SmartSim/blob/develop/smartsim/_core/_cli/build.py reaches out to the internet for many tasks. Some of these can be avoided with the --config-dir argument to smart build but not all.

Justification

Users on air-gapped systems

Implementation Strategy

Have build.py check the config json for the Redis, pip, etc. source.