Form/List: fix swapped right/bottom in scissor area

Fixes rendering bug in the list control (regression by commit
f6728bed).
Screen/OpenGL: support display rotation via glRotatef()

Only enabled on pure EGL targets, i.e. Raspberry Pi and Cubieboard.
Implements TRAC #3238.
Makefile: link test programs without Hardware/RotateDisplay.cpp

.. unless TARGET=KOBO.
Hardware/DisplayRotate: use UIGlobals::GetMainWindow()
manual: add section about Raspberry Pi and Cubieboard
Makefile: use /dev/input/event* on Raspberry Pi and Cubieboard

Implements TRAC #3179.