Rename macro elasticity label and remove dropdown menu in its result page

[GoFroggyRun]

This PR fixes #673 and #683. The new page/button would look something like:

and

and finally

[martinholmer]

@GoFroggyRun, your pull request #684 looks good as far as it goes.
Can you also change the table title (which appears just above the table) along the lines suggested by this 673 comment?

[GoFroggyRun]

@martinholmer thanks for catching this. I changed the title to Percentage Change in GDP:

[martinholmer]

@GoFroggyRun said:

I changed the title to Percentage Change in GDP.

Well, I guess the terms for different parts of a table can be confusing.

I would say that in commit 06f3747 you changed the row label, not the title.

What I would call the title is right above the year table row.

What I was asking you to do was to change Elasticity of GDP wrt 1 - Average Marginal Tax Rate to something like Percentage Change in GDP.

The current title is simply incorrect. The table does not contain elasticities (the one assumed elasticity was specified on the Macro-Elasticity input parameter page) but rather contains the proportional change in GDP caused by the interaction of the assumed elasticity and the change in the average marginal tax rate.

Sorry about the confusion in my earlier request.

But we do need to change the incorrect title.

@MattHJensen @Amy-Xu @hdoupe

[martinholmer]

Commit b27c6fa looks great! Thanks, @GoFroggyRun, and sorry for my confusing suggestions.

[GoFroggyRun]

@martinholmer my bad, I thought your intention were to un-symbolize the % sign. I reverted the row label change and updated the title:

[hdoupe]

@GoFroggyRun LGTM. Is this ready to merge?

[GoFroggyRun]

Yep @hdoupe