deploy for ns-sandbox

[yachang]

trigger the travis deploy by commit to a sandbox branch.

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This change is 

[stephen-soltesz]

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Reviewed 1 of 1 files at r1.
Review status: all files reviewed at latest revision, all discussions resolved.

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.travis.yml, line 39 at r1 (raw file):

    repo: m-lab/mlab-ns
    all_branches: true
    condition: $TRAVIS_BRANCH == ns-sandbox && $TRAVIS_EVENT_TYPE == push

Please use the same convention as other repos where the pattern is sandbox-*.

Please place this deploy target first in order, so the sequence is: sandbox (unreviewed), master (reviewed), production (tagged).

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