[Pharo-dev] [update 2.0] #20613

[Marcus Denker]

20613
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11132 Backport to 2.0: Convert MetacelloConfigurationBrowser to Spec
        https://pharo.fogbugz.com/f/cases/11132


Diff information:
http://ss3.gemstone.com/ss/Pharo20/Tools-MarcusDenker.1062.diff