Campvis Core Dll

* Fixed duplicate symbols of template specialized TextFileParser::readAndParseItems<TextFileParser::ItemSeparatorLines> due to forced inline

Campvis Core Dll

refs #377

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

Tgt Dll

refs #376

Added C4251 to the ignore list for MSVC warnings, occuring due to missing template instantiations of the standard library used in public interfaces of tgt and campvis code. Even though articles such as <http://support.microsoft.com/kb/168958/en-us> provide a clean solution to fix these warnings, I decided that exporting bazillions of std library templates is not worth the effort. As we do not plan to ship TGT without the rest to a variety of systems, the missing exports won't be a problem.
BTW: The original tgt library build scripts also deactivate the warning. :)

closes #376

Closes #387: LogViewerWidget now has a checkbox to select the minimum log level to display. Filtering is performed in widget. Checkboxes to enable/disable each log level, however, seemed to be overkill. If one really wants such specific filtering, he/she can use the filter text box.

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

* Fixed bug introduced in 8a8f9bba: Mouse wheel handler was modifying wrong slices
* Updated README.md

To build CAMPVis using NMake one had to manually copy several external
DLLs into the CMake output directory. There were 2 reasons for that:
- our macros treated NMake as a compiler and didn't try to detect what
  compiler NMake will actually use; as a result, they couldn't find the
  right external DLLs for NMake-based builds
- Visual Studio manages build types independently of CMake and always
  outputs into a build-type-specific sub-directory of the CMake output
  directory — that's where we place external DLLs; NMake, on the other
  hand, relies on CMake for build type selection and will output
  directly into the CMake output directory; due to this discrepancy,
  NMake-based builds couldn't find the external DLLs that were copied
  into the build directory

As many popular IDEs (e.g. Qt Creator, Code::Blocks, Eclipse CDT) rely
on NMake to build projects on Windows, it makes sense to have a working
support for NMake in our build system.

Update our compiler detection macros and adjust the CMake output
directory to match that of Visual Studio when NMake is used to improve
the support for NMake-based builds.

* Fixed orientation of XY-slice (flipped along Y axis)
* Implemented background for raycasting result
* Fixed sum for volume rendering integral evaluation in simpleraycaster.frag

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

Added to missing TGT_API definitions. campvis-application now successfully builds and links tgt. Got bazillions of C4251 warnings though.

Removed oblivious tgt::QtContextManager and merged functionality into tgt::GLCanvas and tgt::GlContextManager. Meanwhile, improved OpenGL context initialization and pipeline creation in CampvisApplication.

This commit explicitly marks TGT to be built as a shared library and
adds several missing TGT_API annotations to TGT classes that are
required by other CAMPVIS modules.

Added s_propertyAdded and s_propertyRemoved signals to PropertyCollection signaling changes to the property list. PropertyCollectionWidget listens to them and updates the GUI on the fly.

* fixed shader (de)activation in AbstractTransferFunction::bind()

Merge branch 'fix-warnings' of /mnt/bigone/git/repositories/sebastian.poelsterl/campvis into development

Merge branch 'shared-libs' of /mnt/bigone/git/repositories/sebastian.poelsterl/campvis into development

* Fixes #362: assignment used instead of comparison
* slight update in GlMorphologyFilter

Affected classes:
- Columbia1
- AdvancedUsFusion
- StrainFiberRenderer
- SimilarityMeasure
- GeometryRenderer
- DataContainerFileLoaderWidget
- DataContainerInspectorCanva