Review Request: Updated release tag format in the release script to use the new 0.12.0-rc1 style formatting.

[Ben Mahler]

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This is an automatically generated e-mail. To reply, visit:
https://reviews.apache.org/r/11786/
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Review request for mesos, Chris Mattmann, Benjamin Hindman, and Vinod Kone.


Description
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As per discussion on the mailing list, going forward we will be using a 
<VERSION>-rc<NUMBER> tag format.


Diffs
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  support/release.sh ef651a2681c98ca4fde1d438b3dd1993d989ca4a 

Diff: https://reviews.apache.org/r/11786/diff/


Testing
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Thanks,

Ben Mahler