Description of problem:
In document list view, clicking the column header "Complete" should sort by the number of "complete". However, if you clicked other columns before, the actual result is sorted by that column instead.


Version-Release number of selected component (if applicable):
Zanata version 3.0.0-SNAPSHOT (20130607-1221)

How reproducible:
Always

Steps to Reproduce:
1. Navigate to document list view of any project that has many documents.
2. Click at any other column that make the "Complete" column unsorted.
3. Click at "Complete"

Actual results:
The documents are sorted by the column you choose on step 2.

Expected results:
The documents should be sorted by "Completed".

Additional info: