This reverts commits:

c721304a
885d908e
a0909989
fb4ad59d
0a9a67cf
0d1624d4
d018cfd5
0504fdd0
a2fd10fe

Conflicts:

	src/plugins/cpptools/cppcodecompletion.cpp

Reviewed-by: Roberto Raggi

Introduced UndefinedType class to replace null pointer.

Done with Roberto Raggi

RevBy:    As discussed with Nigel Hietala
Details:
The following changes have been applied:
* Mac now has hover on panel buttons and combo box
* More emphasis on combobox divider lines
* Arrow up/down is used for Mac/Gtk+ styles

These checks are necessary cause of a recent change in the C++ engine.

Reviewed-by: Roberto Raggi

    Details:  setCurrentEditor was sudddenly private

When completing, don't insert "();" characters when they're already
there. Skip them instead.

Conflicts:
	src/plugins/subversion/subversionplugin.cpp

Task:     - 243147
RevBy:    - Thorbjørn
Details:  - Crash occurred in case there actually is no "current
project", e.g. because the current file doesn't appear in a project.

RevBy: Eike

Reviewed-by: Friedemann Kleint

Task: 238143

Details: Also remove unused change number dialog.

    Details:  patch suggested by Bart van Deenen

RevBy:    - hjk