Everything what was in src/ is now in src/Corrade, everything from
src/Plugins is now in src/MagnumPlugins, everything from external/ is in
src/MagnumExternal. Added new CMakeLists.txt file and updated the other
ones for the moves, no other change was made. If MAGNUM_BUILD_DEPRECATED
is set, everything compiles and installs like previously except for the
plugins, which are now in MagnumPlugins and not in Magnum/Plugins.
Don't do anything to respond to viewport size by default, as the window
has fixed size in most cases anyway (always fullscreen, canvas of fixed
size in browser etc.). Makes the initial implementation requirements
much simpler and shorter.
* The default (empty) implementation of virtuals shouldn't be called,
thus this effectively protects the user from doing it.
* Only the application itself knows best when and how to call
rendering-related functions such as swapBuffers() and redraw(), thus
they are protected.
* Functions for setting up fullscreen or hiding the mouse may be called
from user code outside the application, thus they are kept public.
Better API for handling more than one application screens (context
switching, event propagation etc.). Taken from Push The Box, updated to
current coding style and templated.
Vladimír Vondruš