Good afternoon partners

I have cloned from gitub the diagnostic stack into my catkinws/src because it was what fixed my problem with making work usbcam (solved time ago here http://answers.ros.org/question/118736/solvedproblem-with-rosmake-and-rosrun-usb_cam-usb_cam_node/)

Now we are working with another one (we are a group os students) and when I try to rebuild our the catkin_ws we are getting some (we think) dependencies issues.

First we are getting

CMake Error at /opt/ros/groovy/share/catkin/cmake/catkinConfig.cmake:72 (find_package):
Could not find a package configuration file provided by "pluginlib" with any of the following names:
pluginlibConfig.cmake
pluginlib-config.cmake                                                                           Add the installation prefix of "pluginlib" to CMAKE_PREFIX_PATH or set   "pluginlib_DIR" to a directory containing one of the above files.                                                        If   "pluginlib" provides a separate development package or SDK, be sure it has   been installed Call Stack (most recent call first): diagnostics/diagnostic_aggregator/CMakeLists.txt:6 (find_package)

After this we have tryed to clone from github "pluginlib" and tryed to rebuild catkin but we it has dependencies with ClassLoader (similiar to the specified above but with classloader . . .) wich if we clone from github and try to catkin_make again we get another dependencie with Paco ...

We don´t know what can we do because a weeks ago we were able to set up this withouts this problems ...

Can you help us please?