[Bf-docboard] Manual scope

[Campbell Barton]

It was suggested by @el_diablo that we might consider restricting the
manual to being a reference manual.

see:
http://blenderartists.org/forum/showthread.php?360263-Blender-User-Manual-Official-Call-for-Help!&p=2803818&viewfull=1#post2803818

This doesn't mean we have to make this simply lists of button
descriptions, we should still make this text for users and give some
guidance (usage info and tips).

Examples of pages I'd consider reasonable for a 'reference manual'

- https://www.blender.org/manual/modeling/meshes/editing/subdividing/knife_subdivide.html
- https://www.blender.org/manual/modifiers/generate/solidify.html
- https://www.blender.org/manual/getting_started/basics/interface/buttons_and_controls.html

This means we wouldn't attempt anything like tutorials or howto's.

The main reasons I suggest this is...

- So far we only have a small group of active writers.
- This is what the manual is for the mostpart anyway.
- The few tutorials from the wiki were OK (at best),
... Youtube, blender.stackexchange & dedicated tutorial sites are far
better suited to helping users with spesific interests.
- This is something developers can keep up tp date when functionality
is changed, without giving us pages of text to maintain.

-- 
- Campbell