The recipes are supposed to cross-compile and install the chatter
example. In this commit, the recipe do not contain any dependencies
and configure does not run through yet.

This commit moves the description of previous uses in a separate file,
adds the typical information for a README of an OpenEmbedded layer and
describes the usage for the roscore image recipe.

Instead of maintaining a copy of the tinyxml recipe from the meta-oe layer, we
require that the installation also includes the meta-oe layer.
We updated the README accordingly and also updated the description of the
current setup. We also updated and tuned the CONTENT file.

This commit resolves issue #45.

some minor improvements towards running roscore

The rosversion command requires that the package.xml are available at
run time. The rosversion command is used when starting roscore.

adding some runtime dependencies

The recipe python-pprint rdepends on python-io. As this was not reflected in
the oe-core repository, we added the dependency in genmsg.
Now after the commit abe7bf9992e298f1b53e790eee7b064a9e4e8589 in oe-core,
we can remove the runtime dependency in genmsg.

This commit resolves issue #54.

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

The topic-tools fails during the do_compile step at:
.../sysroots/x86_64-linux/usr/lib/libboost_thread-mt.so: could not read symbols: File in wrong format

The failure comes from the rostest-native package which delivers a
header file with boost dependencies and therefore add the relevant
library to the link path. Add rostest to the DEPENDS to use the
header and libraries from the cross sysroot and keep the native
rostest for the binary.

Fixed #51

Signed-off-by: Stefan Herbrechtsmeier <stefan@herbrechtsmeier.net>

This commit provides a recipe for a core image to start roscore, and
also tunes the README.

For starting roscore, it requires a number of runtime dependencies.
At the moment, all runtime dependencies, even recursive runtime dependencies,
are added only in the roslaunch recipe. Hence, the recipe contains all
runtime dependencies.
At a later stage, one should move the recursive runtime dependencies into
the appropriate recipes.

In the topic-tools recipe, a QA error was raised as the .debug files were put
into the main package. By adding this line in the catkin class, the files are
now placed in the dbg package.

catkin.bbclass: Stage /usr/etc sysroot direcotry 

The CMake generate_messages function from the genmsg package
detects the installed message generators via files in the
/usr/etc/ros/genmsg directory. Stage the /usr/etc directory
manually as it is not a common path.

Fixed #50

Signed-off-by: Stefan Herbrechtsmeier <stefan@herbrechtsmeier.net>

The roscpp-core package is a meta-package. This meta-package and the concept
meta-package in general is not used for any purpose in our layer.

Since its initial contribution in f73e30ae,
the topic-tools had an untested md5 hash for the license check.

Minor organisation improvements

CONTENTS: reducing the CONTENTS file to a general description of some files and the basic directories

Minor improvement in message_filters