Promoting m_static to all SceneCacheNodes
making a unified sceneParmChangedCallback
Added objectOnly toggle to SOP_SceneCacheSource.

Using it to prevent diving into the hierarchy when we really just want to evaluate the current level,
and to determine correct animated/static state.
OBJ_SceneCacheNode is always animated (temporarily).

This is safer until we get some feedback from SESI and can track down the drawing update bug properly.
Correctly transforming GR_CortexPrimitive at render time
Fixed OBJ time dependency issues.

Time dependency has a different meaning in OBJs as in SOPs. In OBJs, a node may be time dependant simply because its parent is, since that effects its world matrix. Since Houdini tries to encourage every OBJ to be static, the solution is to believe Houdini when we're told an OBJ is animated. We now only update time dependency of OBJs when Houdini thinks the node is static, but we know otherwise.
Re-rooting caches with top level objects.

Users found it annoying to name a single piece of geo (or put it in a subnet) just so they can cache it. We now detect top level geo and automatically name it based on the OBJ node name.
FromHoudiniGroupConverter ignores internal groups.

This fixes a bug where the group converter would take preference just because of the selection state. I've verified the fix, but unfortunately I can't write a test case, because there doesn't appear to be any way to create internal groups from python...
Added copyright notices.
Fixed a few bugs that were causing crashes.
Added support for TCL expressions within the file path.
Merge pull request #75 from andrewkaufman/timeDependencyIssues

Houdini SOP Time Dependency Issues
Fixed MurmurHash bug where empty strings had no effect on a hash.

The terminating null character is now considered to be part of the string. This is consistent with the general principle that the low level MurmurHash code should hash the contents of memory (with type information provided only to allow byte order to be dealt with properly).

It could be argued that the other array hashes should also include some sort of terminator to allow empty arrays to have some effect on the hash, but I'm not sure that that's right. At the low level I would consider that they shouldn't, because then they represent more than what's there in memory, and at the high level with VectorData we have additional information to ensure the hash changes anyway.
fixing bug with local variable
Merge pull request #76 from andrewkaufman/ropAutoRoot

Re-rooting Houdini caches with top level objects
Connecting indirect inputs for subnets

When expanding OBJ_SceneCacheTransforms, the child nodes will be connected to the subnet indirect input.
Auto-layout of expanded nodes
File parms channel reference their parent
SOP and Geo Path parms channel reference their parent
fixed crash in SOP info text
Implemented per-vertex Cs for IECoreGL::PointsPrimitive.
Adding interruptors for SceneCache nodes.

Expanding an OBJ_SceneCacheTransform and cooking a SOP_SceneCacheSource can now be interrupted using the escape key.