Issue #1987066 by Kevin Morse, JohnAlbin, rteijeiro, echoz, ry5n: Rename files to match CSS file naming convention.

- Issue #1324058 by isay, barraponto, shameemkm: Fixed forum-rtl.css does not overide #forum div.indent from margin-left to margin-right.

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.

- Patch #821672 by dereine, mgifford, andypost, Damien Tournoud: forum icons not accessible to screen-reader users and forum icons not using sprites.

#145737 by yhager, documentation cleaned up by myself: add support for RTL CSS overrides and default RTL CSS override files for modules
Note: properties, which are different in the RTL display are marked with /* LTR */ in default CSS files now,
so maintainers remember that changing them should also have an effect on RTL CSS files.

This should open the way for better RTL (right-to-left written) language (such as Arabic and Hebrew) support.