SciDAVis - Improvements SVN-temp

- changed Doxyfile according to Knut's suggestions

- fixed wrong email address in the manual

Changes to FitDialog:
- fixed crash due to inappropriate if condition
- fixed some button signal/slot connections

- Tentatively turned several comments into doxygen groups.
Could do with some regrouping and sorting.
- Misc documentation cleanups.
- Fixed show/hide actions for dock windows.

- ported the rest of the changes up to version 0.8.7-3 into the trunk

- ported all changes up to rev 186 into the trunk

- ported changes up to rev 183 into the trunk
(ignored all changes to README.html, translations and manual)

- added some documentation
- fixed a problem with ASCII imports
- fixed a problem with analysis operations
- removed handling of QEvent::Paint from CanvasPicker::eventFilter;
in Qt4 this /caused/ recursive repaints

Fixed bugs in ImportDialog and exportDialog.cpp and improved these 2 dialogs.

Ported Plot3DDialog to Qt4 and improved FitDialog.