python-numpy: new package

This patch add NumPy package for python.

Since Fortran support has been deprecated in Buildroot since the 2013.11
release, and because most of the external toolchains do not provide a
Fortran compiler, it is necessary to explicity disable Fortran compiler
to avoid catching the one from the host system if any.

We also need to fill a site.cfg file to tell NumPy build-system where
it should looking for BLAS and LAPACK libraries.

Signed-off-by: Samuel Martin <s.martin49@gmail.com>
opencv: bump to version 2.4.8

This patch bumps OpenCV version and does a number of cleanup in the
opencv.mk files:
- add an extract command because the source archive is only available
  under zip format since this 2.4.8 release. Since there is no default
  extract command for zip archive, we have to define it;
- add license details;
- add new modules options and update existing ones;
- update SSE support;
- sort and reorder the configure options (to make easier future package
  update);
- clean redundant C++ dependency (in the Qt knob).

However, it does not add any new 3rd-party support for the followings:
- jasper support;
- python/numpy support;
- Qt4 and Qt5 support (since the 2.4.6 release), so only Qt4 support is
  supported in this patch;
- optional libv4l dependency (since 2.4.7 release).
These will be addressed in followup patches.

Signed-off-by: Samuel Martin <s.martin49@gmail.com>
opencv: rework V4L/libv4l support

Starting with the 2.4.7 release, for V4L support, OpenCV does not
requires a libv4l dependency for its V4L support.

So, it now provides 2 distincts knobs for this: WITH_V4L and a new
one: WITH_LIBV4L.

This patch takes advantage of this new knob and libv4l support is
now automatically enabled if only the libv4l package is enabled.

Signed-off-by: Samuel Martin <s.martin49@gmail.com>
opencv: add jasper support

Signed-off-by: Samuel Martin <s.martin49@gmail.com>
opencv: add Qt5 support

Starting with the 2.4.6 release, OpenCV supports both Qt4 and Qt5,
but only one can be enable at the same time.

Since Buildroot does not support Qt4/Qt5 co-existence, we keep the Qt
support knob as a boolean, but make it depend on BR2_PACKAGE_QT or
BR2_PACKAGE_QT5, and automatically uses the enabled one.

Note that we usually use 'select ...' to express the dependencies
between packages, but in this case, we cannot since the Qt4/Qt5
co-existence exclusion is not handled by a simple choice, but by a
dependency. This makes impossible using 'select ...' for the Qt
support knob without triggering a circular dependency at the kconfig
level.

Besides, we already use 'depends on ...' to express the dependencies
with some "big" packages (like xorg or libgtk2). qt or qt5* packages
are fairly big. So, I don't think it will hurt that much to use a
'depends on ...' statement in this case.

Signed-off-by: Samuel Martin <s.martin49@gmail.com>
python-numpy: add install-staging command

Some packages may include headers provided by python-numpy package.
So, also install it in the sysroot.

Signed-off-by: Samuel Martin <s.martin49@gmail.com>
opencv: add python/numpy support

Signed-off-by: Samuel Martin <s.martin49@gmail.com>