Merge pull request #48 from bulwahn/master

Minor improvement in message_filters
Merge pull request #49 from bulwahn/master

Minor organisation improvements
topic-tools: Corrected md5 hash of license

Since its initial contribution in f73e30ae40312ea804a58064f7103c297ba6fa15,
the topic-tools had an untested md5 hash for the license check.
roscpp-core: removed currently unneeded recipe for meta-package roscpp-core

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.
README: updating to latest OpenEmbedded Core development with boost patch
catkin.bbclass: adding .debug files to the dbg package

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.
roslaunch: adding all runtime dependencies to get roscore starting up

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.
core-image-ros-groovy-running-roscore: a core image to start roscore

This commit provides a recipe for a core image to start roscore, and
also tunes the README.
README: updating maintainers and contributors due to recent events