I want to sub-theme the Omega theme in the commerce_kickstart-7.x-2.0-rc2 installation but unlike the dev-no-core distribution, there are no Omega or Omega-Kickstart or commerce_kickstart_theme folders under the themes folder. Yet these themes do show up as available themes in the appearance page. So, where is this stuff hidden? Or rather how am I supposed to sub-theme one of these themes in this distribution without the base theme folders existing under the themes folder?