The dashboard column selector was sorting based on the label field which is

empty for many columns and different from the labels shown in the selector for

many others. The result of this was that the list of available columns showed

up in a seemingly random order.
Given that some columns (like the check-box column) include HTML in their

detailed_label, I've split this into two different parameters to __init__:

detailed_label, and detailed_label_html. We sort based on the first, and

display the second.
This requires some changes in Review Board to have everything pass in the data

to __init__ correctly.

Looked at the column selector and saw that everything was in alphabetical

order, even when the column included HTML or other entities at the beginning of

the text.