Builds and runs fine so far, but no elaborate testing done yet. Compiler throws a bunch of C4275 warning, since sigslot:has_slots<> is used in exported classes but is itself not exported. While this is no direct problem for campvis-internal builds, it should still be fixed some time.

refs #377

Extended the DataContainerTreeWidget and its corresponding DataContainerTreeModel to support a second level containing the DataHandles of RenderData and ImageSeries items.

Beautifying VolumeExplorerDemo and VolumeRendererDemo sample rederings by fine tuning transfer functions.

* Added assertion in ImageRepresentationGL constructor checking for matching number of channels

Changed log level of some warnings from DEBUG to WARNING, disabled some verbose debug messages in TGT

* Implemented GeometryDataFactory::createCube() normal generation

* Introducing MultiIndexedGeometry data type
* Introducing GeometryDataFactory::createTeapot()

Completely moved the image data handle and histogram computation from the TF to the TF property. Histogram computation is now thread safe.

 * Introducing campvis::Tensor2<T> type
 * Updated MhdImageReader to support TensorImages

*IMPORTANT FIX* Fixes possible crashes/segfaults when converting OpenGL image representations to local image representations:
 * ImageRepresentationLocal::tryConvert() does not deadlock anymore when called from OpenGL context and converting from GL representation
 * Fixed possible double deletion after converting from OpenGL to local representation due to ambiguous pointer ownership
 * fixed possible out of bounds array write in tgt::Texture::downloadTextureToBuffer()

* Moving to Apache 2.0 license
* Updated AUTHORS.txt

* Updated DepthDarkening to use GlReduction to compute min/max depth

 * added computation of difference image to SimilarityMeasure
 * fixed possible out of bounds access in datacontainerinspectorwidget.cpp
 * added assertions to ImageRepresentationGL constructor

* Fixed pointer inconsistencies in ScopedTypedData and ScopedRepresentation

Cleaned up and slightly revised GeometryData API. Cleared the way for non-value semantics. Introducing GeometryDataFactory, a collection of static methods to create standard geometric primitives.

work on Issue #88: cleaned up VertexArrayObject interface. It's now simpler and more straight-forward.

# Fixing the bugs of the Color Window in the Canvas

# Make a pointer from datacontainerinspectorwidget into datacontainerinspectorcanvas, as we need to call the updateInfoWidget() after updating the color.

# Make the updateInfoWidget() as public to be able to call it.

# Add the Capability to look up the color under the mouse button when one of the mouse buttons is pressed.

Introducing usage of C++11 lambda functions instead of functors in some tbb::parallel_for blocks for better readibility

# Make a pointer from datacontainerinspectorwidget into datacontainerinspectorcanvas, as we need to call the updateInfoWidget() after updating the color.

# Make the updateInfoWidget() as public to be able to call it.

# Add the Capability to look up the color under the mouse button when one of the mouse buttons is pressed.

Fixes -Wignored-qualifiers

Work on Issue #44: Removed GLContext interface and merged functionality into GlCanvas. Introducing abstract (Qt-free) tgt::GlContextManager interface, being implemented by tgt::QtContextManager. Further clean up of related code.

CampvisApplication manages multiple DataContainers, updated PipelineTreeWidget to show correct DataContainer/Pipeline/Processor hierarchy

Removing TBB library from /ext making it fully external (user has to install TBB himself). Adapted CMake files. Adapted include directions