ar_track_alvar 0.5.x only support opencv2, whereas meta-oe provides
opencv3. The ar_track_alvar kinectic versions 0.6.x also support
opencv3, as pointed out in the comment of commit e82747c4 [1].

Therefore, this commit updates ar-track-alvar to version 0.6.1
to resolve #397.

[1] https://github.com/sniekum/ar_track_alvar/commit/e82747c42df3ead0d45bcd84048f6baef04b9f67

.

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

This commit also drops the patch provided upstream, and since
version 0.5.1, the ar_track_alvar package now provides an archive
with more default directory structure.

This commit also corrects the license information in the recipe to
LGPL-2.1.

With the poky-dizzy distribution, the do_rootfs task for
core-image-ros-world fails with:

  ERROR: Unable to install packages. Command '/[...]/build/tmp/sysroots/x86_64-linux/usr/bin/smart --quiet --data-dir=/[...]/core-image-ros-world/1.0-r0/rootfs/var/lib/smart install -y run-postinsts@all packagegroup-core-boot@beaglebone packagegroup-ros-world@all' returned 1:
  error: Can't install ar-track-alvar-0.4.1-r0@cortexa8hf_vfp_neon: no package provides libmedianFilter.so

Build Configuration: poky 1.7.1;
  poky: "dizzy:ec75238f6cc2d2d8d40e0268f6d2acc070cbe9a4";
  meta-openembedded: "dizzy:9efaed99125b1c4324663d9a1b2d3319c74e7278"

To resolve this problem, this commit updates ar-track-alvar to the
latest Hydro version 0.4.2. Unfortunately, there is no archive file
for version 0.4.2, so the recipe uses the git repository with the
commit intended to mark version 0.4.2 to fetch the source code.
Due to the update, this commit also removes the upstream-accepted
patch file from this repository here.

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

After running oe-stylize.py on all recipes in recipes-ros, this
commit improves the formatting of some recipes.

To achieve this, I executed these commands in recipes-ros:
find . -name *.bb | sed 's#\(.*\)#./oe-stylize.py \1 > \1_sanitized#' | sh
find . -name *.bb | sed 's#\(.*\)#diff -Naur \1 \1_sanitized#' | sh > diffs

Then, I manually inspected the diffs file, and improved the
recipes.

For the DESCRIPTION line in the addressed recipes, the line width
of 100 characters was chosen, as the LIC_FILES_CHKSUM line and
SRC_URI line usually are also around about 100 characters long.
Hence, choosing a shorter line width, e.g. 80 characters, would
have only created more line breaks, but not reduced the need to
use a file viewer with which 100 characters line width can be
displayed. For the github file and diff viewer and most editors
on reasonably-sized screens, 100 character line width is no
problem.