A UI for document-local layout information. LyX has supported this for a

A UI for document-local layout information. LyX has supported this for a
while, but without any UI for it. (There has been local layout in the
Customization manual for a long time, in fact.)

Yes, this is an advanced feature. But, absent a layout editor, it is the
one thing that will make it easier, and possible, for "normal users" to
experiment with layout without having to go through reconfiguration,
etc, etc. To keep too many people from shooting themselves, we validate
the layout information before allowing the user to apply it.

git-svn-id: svn://svn.lyx.org/lyx/lyx-devel/trunk@35061 a592a061-630c-0410-9148-cb99ea01b6c8