Description of problem:
When pushing with --merge=import, the translations on server are not overwritten, just like --merge=auto were passed.

Version-Release number of selected component (if applicable):
1.3.0 and commit b9c55fdf519cfb18b95260b71549c875ad8bfc56

How reproducible:
Always

Steps to Reproduce:
1. Assume AboutFedora, version f13, and zh-CN translation are imported.
2. Login though Web UI
3. Goto Project AboutFedora, version 13, locale zh-CN (or equivalent)
4. Visit Document "About_Fedora"
5. Now message list of "About_Fedora" should be showing, 
   click on "Copy from Source" on row 1, and Save as Approved
6. zanata push --project-type=podir --merge=import --push-trans


Actual results:
After reload, row 1 has not been overwritten by the translation from original project repository.

Expected results:
After reload, row 1 should be overwritten by the translation from original project repository.

Additional info:
maven client pushing with -Dzanata.merge=import works