Unable to fetch Releases logs on UI

[Andrey Sledzinskiy]

Reproduced on {

    "build_id": "2014-06-04_09-16-08",
    "mirantis": "yes",
    "build_number": "341",
    "nailgun_sha": "a828d6b7610f872980d5a2113774f1cda6f6810b",
    "ostf_sha": "c959aa55f83fe2555cf2d382559271c7a9b17467",
    "fuelmain_sha": "7ed0f85acc0bab4b9157703a618b8cc9fd7de3e1",
    "astute_sha": "55df06b2e84fa5d71a1cc0e78dbccab5db29d968",
    "release": "4.1B",
    "fuellib_sha": "0e96fc5a340cd57f75c454ea8536471379299494"

}

Steps:
1. Create cluster with default values
2. Open Logs tab
3. Select Releases in source
4. Click 'show'

Expected - releases logs are shown
Actual - get 'Unable to fetch logs' (screen is attached)

[Julia Aranovich (jkirnosova)]

This behaviour is caused by 404 Not Found response on GET /api/logs?node=&source=puppet&level=INFO&truncate_log=true

GET /api/logs/sources gives source {id: 'puppet', name: 'Releases', ...}, so I think js code works correctly.