The recent versions of the rosbridge_library package does not depend
on python-pytz anymore. So, this commit removes the dependency in
the recipe file and removes the now unneeded python-pytz recipe.

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

This commit adds recipes for rosbridge_suite and its dependencies.
Its main content is based on the commits of pull request #364 by
Christoph Schultz.

As maintainer, Lukas Bulwahn just included the contributions
with a proper commit message, added the new packages to the
packagegroup-ros-world, and slightly improved the line breaking.