Minimal reorganization

[ivanpauno]

• Deleted files folder, including some files related with the old app build process.
• Moved pluginlib_helper from files to scripts.
• Stop downloading rospkg, it's already installed inside the docker container.
• Moved toolchain file inside a "cmake" folder.
• Updated scripts with this changes.

[ivanpauno]

Codewise looks good; I haven't tested it yet. I have a doubt about this point:

Stop downloading rospkg, it's already installed inside the docker container.

rospkg is also downloaded within the catkin workspace, but I don't see how it's accessible to pluginlib helper at the time the script is called. Am I missing something?

rospkg was downloaded directly inside "files" folder before, and was added as a system library download (not in the catkin_ws) in the last reorganization, and copied to "files" folder from there.

It was used only in "plugin_collect.py", specifying from which folder import. It's not really needed, as is part of the packages downloaded with ros-core (in /usr/lib/python2.7/dist-packages/rospkg)