hobo model index page shows the "name" column always as first. 

this pull request fixes the following bug:
on the hobo model index page the first column was always set to the "name" column. In the case that the :name field did not exist, the first field was overridden and disappeared.

My patch assumes the following:
- that field_names contains strings                                                                                  
- that name_attribute returns a symbol 

note: on the page http://hobocentral.net/manual/model#name
name_attribute returns a symbol.
I think in the current release only a string is returned.

I did not write any tests for this patch