Sort Key for HABTM should be comma seperated string instead of Array

[mark579]

This was creating issues doing a dump because Arel Table expects a string for the order argument and was receiving an Array.

[mark579]

Build Failures don't appear to be related to the code.

[mark579]

Any thoughts on getting this merged?

[dnrce]

Thanks for raising this! Arel accepts multiple arguments to order, but they need to be provided separately rather than in an Array.

OK:

2.3.1 :002 > Arel::Table.new('normal_table').order('id').orders
 => ["id"]

Not OK:

2.3.1 :003 > Arel::Table.new('habtm_table').order(['first_id', 'second_id']).orders
 => [["first_id", "second_id"]]

Fixed:

2.3.1 :004 > Arel::Table.new('habtm_table').order(*['first_id', 'second_id']).orders
 => ["first_id", "second_id"]

I've corrected this in #119.

[mark579]

Nice! Thank you.