ResourceLoader: new template ConstBuffer instead of std::pair
ResourceLoader: use ConstBuffer in the static resource arrays

Don't convert from pointer+size to ConstBuffer at runtime.
Screen/Bitmap: make the class "final"
Screen/Bitmap: enable the SurfaceListener code only on Android

On other OpenGL targets, we have no real Reload() implementation, and
therefore let's disable it completely instead of this half-baked
code.  One day, we'll have a real and portable implementation.
OpenGL/Bitmap: move LoadStretch() to ResourceBitmap.cpp

Decouple resources and the Bitmap class some more to reduce
dependencies.
Makefile: move ResourceLoader.cpp and XCSoar.rc to libresource.a

Simplify building programs that use resources.
Makefile: use "ld" to generate *.o files from resources

Eliminate the intermediate step that generates huge constexpr C++
arrays.
ResourceLoader: disable Load(unsigned) on Android

Not used on Android, because the numeric resources are bitmaps that
are handled natively with Android's Java API.  This commit has no
runtime effect, it just ensures at compile time that this function
must not be used on Android.
Makefile: move flags to SCREEN_CPPFLAGS_INTERNAL
Screen/Bitmap: include cleanup
Screen/Bitmap: move code to Load(ConstBuffer)
*: include cleanup
Makefile: restore dependency from resource_data.h on $(RESOURCE_FILES)

This is necessary because tools/GenerateResources.pl checks the file
size.
po: update Japanese translation
PlaneListDialog: don't translate space
*: remove unnecessary resource.h #includes
Screen/Bitmap: add constructor with ConstBuffer<void>
resource.h: add macro MAKE_RESOURCE()

Rename to Resources.hpp and auto-generate the file resource.h.
Prepare upcoming resource optimisations.
Makefile: pass -Ioutput/include to windres

Necessary to #include resource.h.
Makefile: use $(OUT)