SciDAVis - Improvements SVN-temp

- Updated to Qwt5.0.0-rc0.
- Fixed misalignment between in and out ticks in 2D plots.
- Fixed saving/restoring of 2D plot markers to/from project files.
- Rewritten ImageMarker class.

huge commit:
- merged all changes to the Qt3 version
up to 0.8.6-2 into the trunk
- ported all merged lines to Qt4
(most pure Qt4, some using Qt3Support)

- Fixed bugs when drawing Spline curves.
- Added a VerticalSteps plot style.
- Fixed inward ticks drawing in 2D plots.

- Added an Origin-like feature: when plotting a list of columns, if some columns are declared as having yErr or xErr type, they are plotted as error bars.

- tagging version 0.8.7-3

- improved the Python interface to folders
- added documentation for the above

- Fixed bug in NonLinearFit class: setting only one parameter caused crashes.
- Modified TableStatistics behavior so that the user can use them directly for plotting.
- Fixed restoring geometry and creation date of TableStatistics from project files.

- table statistics now react to columns being deleted or renamed

- Defined a new "fit_scale_errors" option in the user global settings and added this option to the configDialog.
- Fixed translation issues in configDialog and translation of the ScriptWindow when the language of the main application is changed by the user.
- Upgraded French and Spanish translations.
- Fixed some compile issues on Windows due to new code in TableStatistics.

- column / row statistics are automatically updated when the base table
is edited
- fixed some sanity checks in ApplicationWindow
- "exit -> yes (save changes) -> cancel" now cancels the exit instead of
discarding the changes
- added support for folders to Python interface
- some minor fixes