Committing Nodes Efficiency Tools to trunk.

'Nodes Efficiency Tools' is a set of several tools that can speed up working with nodes, both compositing and Cycles shaders.
They automate several tasks that by default require many clicks, drags etc.
All of the tools can be accessed via additional panel in node editor properties toolset or by hitting Ctrl-Space keyboard shortcut.
Most of the options however have their own keyboard shortcuts and using them is much more efficient.
You can find all of the info on the wikipage: http://wiki.blender.org/index.php/Extensions:2.6/Py/Scripts/Nodes/Nodes_Efficiency_Tools

Available options are as follows:

Merge selected nodes:
Imagine that you want to 'add' images represented by outputs of some nodes.
Standard way of doing it is to add MIX node, change blend type to 'Add' and link outputs of the nodes accordingly.
With Nodes Efficiency Tools you can select the nodes and hit (Ctrl +) keyboard shortcut.
Proper setup of nodes will be added and links will be made.
Other shortcuts are used for other blend types, you can also use 'Math' nodes for merging and different shortcuts allow to do so.

Batch Change Blend Type or Math Operation:
Hit (Alt-UP ARROW) or (Alt-Down ARROW) to change blend types or math operations of selected nodes.
It's often much quicker than standard way of doing it.
Use additional menu to select the blend type from the list and change types of all selected nodes at once.

Change Factor of Mix Nodes or Mix Shaders:
(Alt-LEFT ARROW), (Alt-RIGHT ARROW) shortcuts allow to change factors of selected Mix nodes or Mix Shader nodes by 0.1.
More precision is gained when we add Shift to the key combination.

Align Nodes:
We can align nodes nicer than by hitting S-X-zero. Even distribution of aligned nodes can be achieved easily. (Shift =)

Copy Settings:
We can copy settings from Active Node to all selected ones.
May be helpful if you want to use exactly the same RGB Curves nodes in different places of your node tree.
This option works with all node types.

Copy Label:
We can copy labels from one node to other nodes with one click.

Swap Nodes:
It's possible to change the node to other type.
Swap easily between 'Mix' and 'Alpha Over' nodes for example or easily change 'Diffuse' Shader to 'Glossy' Shader.

Link Active to Selected:
This option allows to link active node to all selected ones basing on several criteria.
May be extremely helpful when for example re-linking image sources.
We can easily change input Render Layers node to input image (MultiLayerEXR) preserving nodes setup.

All of the options are explained in details in the video tutorial embedded on the wikipage.

[[Split portion of a mixed commit.]]