Add support for string/parameter based Enabled for DeploymentPreference #1361
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Issue #, if available:
#350
Description of changes:
This change allows developers to reference string parameters to enable or disable deployment preferences. Previously, any non-empty string evaluated to true and any empty string evaluated to false.
Description of how you validated changes:
Created new unit tests and ran make test
Checklist:
make prpassesmake prwould not work, asmake black-checkwas failing, even before making my changes. I tried using both python2.7 and python3.6. Any guidance here would be appreciated.examples/2016-10-31By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.