Reformatted plots and reset carbon tax default to 0

[arao53]

Fixes/Addresses:

Resolved LCOW value error and reformatting visualize_results.

Summary/Motivation:

Changes proposed in this PR:

Legal Acknowledgement

By contributing to this software project, I agree to the following terms and conditions for my contribution:

1. I agree my contributions are submitted under the license terms described in the LICENSE.txt file at the top level of this directory.
2. I represent I am authorized to make the contributions and grant the license. If my employer has rights to intellectual property that includes these contributions, I represent that I have received permission to make contributions and grant the required license on behalf of that employer.

[adam-a-a]

@arao53 With regard to the pressure, now that I think about it, the capital cost of the pump will vary by pressure and flow rate (essentially power consumption) unless we specify that the pump should be costed by the design pressure and flow rate of the pump. Not sure if that's the case