roots/roots — pull request #950 by willthemoor (2013-12-29 00:44:02+00:00)
Title: Add Check For Theme Activation Constant

Allows a developer to skip Roots' Theme Activation step by setting a constant:

define('ROOTS_ACTIVATION', FALSE);

From discussion at http://discourse.roots.io/t/disable-activation-page-when-switching-themes/917/