User does not understand function of add/remove columns button

[za158]

Notes from test:

Find out how to filter by sector
Goes first to the company dropdown menu
Then clicks around to a bunch of other stuff
Does not see add/remove columns
When I point her to it she does fine.
She thought that feature was "content-related", not obviously about customizing the display
Clicking on sort instead

[za158]

"having somewhere that provides a list of all of the columns, different options, that was hard to find"

[za158]

@jmelot @brianlove any bright ideas here? all I can think of is (1) change "columns" to "metrics" or "indicators" (2) give the button a brighter blue background, like the sort indicators