python-numpy: drop now superfluous bbappend file

In the meta-ros commit b6080314 (commit date: 2013-11-17) [1], we
add python-numpy_1.7.0.bbappend to provide python-numpy as native
package, as the version update to cv-bridge 1.10.14 needs that.

Coincidentally, Ross Burton added native support to the
python-numpy recipe in the meta-openembedded commit c13c5f40
(commit date: 2013-11-18) [2]. However, the existing bbappend in
meta-ros was still required for use with releases before commit
c13c5f40.

On 2014-01-14, the python-numpy recipe was moved from meta-oe to
openembedded-core (commit a4415f89 and 9bf355cc [3, 4]).
Now, on 2015-12-16, the python-numpy recipe was updated to 1.10.1
(commit 3c3932f3 [5]), and hence, our version-specific bbappend
file fails to apply.

As the native package addition is now in the recipe for over two
years (commit date: 2013-11-18), and we assume all users to work on
versions where the change has been included, we simply drop our now
superfluous bbappend file.

[1] https://github.com/bmwcarit/meta-ros/commit/b6080314504be62c8fbfcb1d583e688448a2f023
[2] http://cgit.openembedded.org/meta-openembedded/commit/?id=c13c5f40160d289bb62538a16900fed30621cb22
[3] http://cgit.openembedded.org/meta-openembedded/commit/?id=a4415f89e533a59ba358f8575d56216d3650e59e
[4] http://cgit.openembedded.org/openembedded-core/commit/?id=9bf355cceaec6ebacdcbcc35f9713ff73e1c85da
[5] http://cgit.openembedded.org/openembedded-core/commit/?id=3c3932f3560c898e32287c8733b61180685ee539



Signed-off-by: Lukas Bulwahn <lukas.bulwahn@oss.bmw-carit.de>