Fix WireframeHelper for BufferGeometries without offsets

by just creating a dummy offset
fix coding style
Improved documentation of ShaderMaterial and RawShaderMaterial
Continue documenting properties/methods of ShaderMaterial
Implemented cross-referencing functions for members
Implemented example cross-referencing from docs
Modified documentation regexes so that link titles can contain spaces and anchors
Add examples of cross-referencing in BufferGeometry
renamed offsets into drawCalls
typo fix
Added new 'world' methods
passing event handlers. see #4807 #4803
Editor: Added headers.
blender exporter: fileextention from ".js" to ".json"
Merge pull request #5428 from jpcloud/dev

blender exporter: file extension from ".js" to ".json"
permute onProgress and onError in TGALoader
Merge pull request #5423 from vincent/dev

passing event handlers. see #4807 #4803
BufferGeometry: Added center placeholder.
Moving THREE.Script to the Editor.
Merge remote-tracking branch 'origin/dev' into dev