clean clone of the project does not build

[mockitoguy]

When I clone vanilla repo, "./gradlew build" fails. It would be nice if it worked out of the box.

Build file '/Users/sfaber/mockito/gradle-bintray-plugin/build.gradle' line: 99

* What went wrong:
A problem occurred evaluating root project 'gradle-bintray-plugin'.
> Could not find property 'bintrayUser' on com.jfrog.bintray.gradle.BintrayExtension_Decorated@404eca05.

[dmolesUC]

I've run into this on other projects that use the bintray plugin. It would be nice if the bintray plugin didn't bother evaluating its configuration till it's actually needed.