Issue #1838156 by ry5n, swentel, sannejanssen: Implement the two-column layout for the new create content page.

Nate Lampton authored Oct 30, 2011 and catch committed Nov 01, 2011

Issue #22336 by quicksketch, scor, boombatower, and rfay. Move all core Drupal files under a core subdirectory.

#610234 by Gábor Hojtsy, ksenzee, cwgordon7, David_Rothstein, seutje, marcvangend, sun, JoshuaRogers, markus_petrux, Bojhan, Rob Loach, Everett Zufelt, drifter, markboulton, leisareichelt, et al: Added Overlay module to core, which shows administrative pages in a JS overlay, retaining context on the front-end site.