The ROS_STACKAGE variable (stack.xml vs. package.xml) does not exist anymore
since ros-fuerte support has been dropped.
Now this is just a regular 'package.xml' file.

- Regen distinfo for fixing the distfile path (ros distfiles now lives in their
  own subdir). PR by Olivier Stasse, thanks!

- Fix minimum ros version >= hydro, since this package is not available on
  groovy.

The package compiles with ros==groovy. However, ros-groovy does not contain
this package, and the ros-realtime-tools dependency will not be met when
PREFER.ros==system.

It is also not currently possible to set a specific PREFER.ros-realtime-tools
default to robotpkg or system automatically depending on the ros version to be
used. So binary packages depending on this one won't built because of the unmet
dependency.

While here, fix a typo in PREFER.ros-realtime-tools and fix files permissions.

- Wrap long lines in DESCR
- Fix HOMEPAGE (actually drop it, since the default in
  meta-pkgs/ros-base/Makefile.common is fine).
- Shorten ROS_COMMENT to ~60 chars
- Drop useless dependency on tinyxml
- Fix typos in depend.mk
- Add a ros>=hydro requirement in the Makefile, since this package is not
  available in groovy. This is currently a show stopper, because robotpkg
  supports only groovy with PREFER.ros=robotpkg, so this package cannot build
  ATM.

First robotpkg release.

This package contains a set of tools that can be used from a hard realtime thread, without breaking the realtime behavior. The tools currently only provides the realtime publisher,
which makes it possible to publish messages to a ROS topic from a realtime thread.