* Again, some layout code cleaning.
* Made assignments more consistent.
I started to write code guidelines in the wiki:
http://wiki.blender.org/index.php/LayoutFiles-Code_Guidelines
Matt/William: You are welcome to change them or add new infos, I will continue on improving them as well in the next few days.
* Fix poll() callback changes in recent commit, note that these have
to work with pinned context too.
* Hide header for context panels in py layout.
* Don't jump back when collapsing a panel, allow the view to be
over some empty space until you scroll back.
* Fix follow context icon, order had to be reversed in icon file.
* ID template now has icon as part of browse button instead of
outside the buttons.
"moving the ID browser into its own panel. Eventually these panels should loose their headers to distinguish them from other, normal panels. Also a few other fixes for bones and armature panels."
* Fix context.cloth, was not being set correct.
* Fix errors with context pinning, scripts should
not assume context.object to be there.
* Always show preview even if e.g. the material is not
set, to keep ID buttons from jumping while you're
using them.
* Added more material buttons by William. Thanks.
I made some minor adjustments and added Specular Shader Model RNA.
* Code cleanup and some consistency tweaks of button files.
Notes: Preview render now only shows up when there is an active world, material, texture or lamp.
* Made sure initial panels with ID Datablocks are shown, even when no block is active.
* Context now allows pinning a datablock, independent of
selection.
* Initial ID browse buttons for most buttons tabs.
* Browsing from world to texture now displays world textures
again, but is a bit of a hack, not sure there is a right
way to do this.
* There's a button to switch between active materials and
textures now, only temporary though.
* There's some code to put context part in own region,
disabled still because it doesn't work that well yet.
* turned some slider UI controls back into number fields
Note: Sliders should only be used when representing a property that's
conceptually a percentage or ratio. For arbitrary numbers, use a number field.
For example, a lamp's energy can theoretically be anything - 0.1, 3.5, 125.0, it
doesn't matter - it's just a number, not a percentage. So this should be a
number field.
* Fix buttons jumping around when resizing and zoom. Part of this was
adding a tiny a 0.001f offset in UI_view2d_view_ortho, otherwise the
rounding is unpredictable (used to be 0.375f, but that was disabled).
* Fix various issues with zooming, panning panels. V2D_LOCKOFS_X/Y is
now taken into account in more places in the view2d code, to avoid
zooming into the center or panning out of the view.
* Remove "Free" align mode in buttons window (it's not really useful).
* View3D/Graph/Image editors now use the same PanelType system as the
buttons window, means some deprecated panel code could be removed.
* Some small visual tweaks for panels.
* View 2D Reset operator (Home key), to reset zoom and panning for panels.
* Added argument to set number buttons as sliders (slider=True for itemR).
* Ignore labels for button alignment (doesn't look right).
* Fix some use of context.main in py scripts, should get data from active
object instead.
* Fix autotexspace -> auto_texspace in py script.
* Added new modifier tab.
* Fixed problems when no object was selected after delete.
* Added initial Armature, Bone, Curve and Font panels, by William Reynish (Billrey). Thanks!
* Small RNA changes
* Commit revision 20240 and 20268 from trunk. ("Mouse wheel zoom lost after rendering.")
