* Rename all member variables and methods that reference the cross hair
code in draw panel object from cursor to cross hair to eliminate confusion
between the two concepts.
* Rename cursor capture call backs in draw panel object to improve code
readability.
* Create helper class for turning off the cross hair while drawing.
* Remove redundant block clear code.
* Remove redundant mouse capture call back reset code when end capture
call back is called.
* Remove unused function definitions in base draw frame object.
* Lots of minor coding policy and doxygen comment fixes.
* Remove unused member variable m_SizeVisu from base screen object.
* Move nearest grid position code into base screen object.
* Add get cursor position method to base screen object.
* Add position parameter to OnHotKey method in base draw frame and all
derived objects.
* Pass logical position on left mouse button click and double click
events instead of device position.
* Pass logical position to on right mouse button click instead of device
position.
* Use logical event position parameter for locating items in EESchema
instead of the stored position.
* Remove unused position parameter when displaying component edit dialog
in EESchema.
* Comment out debugging macro in eeschema/template_field_names.cpp that was
preventing debug builds using wxWidgets 2.8.x.