SciDAVis - Improvements SVN-temp

- started to integrate the new Table class into the
application
Status: It compiles and runs but a lot of functionality
is disabled at the moment, many things are under heavy
construction. At least testing inside the application
is possible now.

- did some left over renaming
- added missing timer stop to main.cpp

- extended the table command test program
- fixed some bugs related to table commands

- implemented several more table commands
- made some additions to Interval and IntervalAttribute
that are used in the new table commands
- updated the table command test program
- some small improvements to TableModel

- Made icon background transparent, which required some other changes in order to go well with different backgrounds.
- Simplified splash screen and added the logo to it.
- Fixed some details.

- improved loading/saving of gzipped project files

- implemented handling of selections in TableView

- layer buttons now have their own context menu

- simplified/improved MatrixDialog to be more intuitive

- fixed "enumerate all to the right" in TableDialog
- removed 2 obsolete xpms in PlotDialog
- fixed some references to icons