(Updated with some early changes) Apple is now distributing a seventh developer preview of OS X Yosemite, as well as matching betas of Xcode 6, OS X Server 4.0, and Configurator 1.6. Any changes to Yosemite are unmentioned in release notes, but will probably be uncovered within the next few days. The last preview build of Yosemite was released roughly two weeks ago….