https://issues.liferay.com/browse/LRDOCS-866 

https://issues.liferay.com/browse/LRDOCS-866

Updated the Layout templates section of the Dev Guide to 6.2, explained the use of Alloy Bootstrap's 12 column grid layout, removed the sections on Dev Studio's layout template editor, added instructions on creating layout templates in text editor. (Dev Studio 2.0 does not support visual layout template editor, maybe future versions will)