SciDAVis - Improvements SVN-temp

- fixed another crash in the project loading code

- improved locale support in FitDialog
- fixed crash when appending a project
- "column options" and "set column values" dialogs:
added a combo box for direct column selection and
rearranged the layout a little bit
- fixed crash when selecting "set column values" in
a table with no columns

- ASCII import dialog: changed "import decimal separators" to "use custom
decimal separator"
- ASCII import dialog: moved the "help" button into the lower right corner
- ASCII import dialog und preferences dialog: changed "system locale setting"
to "default (...)"
- preferences dialog: added a preview box for the numeric format
- column options and set column values dialog: changed the "<<" and ">>"
buttons to "<< prev." and "next >>"
- added support for custom QLocale handling in the fit wizard
- renamed the "data" menu to "tools"
- added a submenu to show/hide toolbars to the "view" menu

- made matrix and table loading/saving independent
of the decimal separator settings

Fixed some details on the website.

Fixed News by including them statically.

- Did a better screenshot for the front page.
- Added some basic information on contributing code and documentation.
- Added a credits page.
- Disabled pages on translating and packaging until we have some content there.

- removing dublicate logo files

- Major update to the installation instructions.
- Added logo (SVG and PNG).
- Changed defaults in scidavis/scidavis.pro in order to make installation easier for new users.
- Renamed license file to gpl.txt (the name it is distributed under by the FSF).
- Small fix in ExtensibleFileDialog.

Some details cleaned up.