Emission intensity: Change the line for scenario to be visible when overlap

[MonikaFu]

With #171 a dodge was implemented for emission intensity line for which I understand the logic but which I think is confusing. For example here is looks as if the plots don't start at the same time point:

I think a better solution will be to make the portfolio line more prominent and always visible through:

• bigger dot marker for data point
• solid line

And the scenario line less visible through:

• smaller marker
• dashed line

[MonikaFu]

FYI @jdhoffa

[jdhoffa]

Hmm, I don't believe any of the solutions identified above would address the original problem, which arises when the Portfolio and Scenario lines truly follow an identical trajectory:
#142 (comment)

[MonikaFu]

With the solution proposed above you would see a dashed line of scenario over solid line for portfolio with a smaller scenario marker over a bigger marker for portfolio so both would be visible.