fix issue #1131

[kz33]

Fixing issue：#1131

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[kz33]

@googlebot I signed it!

[liyinan926]

Please also update README.md for the new config option.

[liyinan926]

Please update the chart version.

[kz33]

Hi @liyinan926
Can you help me see the reason why CI hasn't passed it? Thanks so much !

[liyinan926]

Can you do some dummy commit to trigger the Travis build?

[liyinan926]

LGTM