Folders here are copies of release folders of individual projects. In order to update, first go into the target folder, and use svn sync merge to sync the folder with the original one. For example, update ParallelIterator’s download stuff.
$ cd ParallelIterator
$ svn merge ^/ParallelIterator/trunk/release
Because plugins have slightly different folder structure, here is an example:
$ cd PyjamaEclipsePlugin
$ svn merge ^/PyjamaEclipsePlugin/trunk/PyjamaEclipsePlugin/release
Or you can use script “updateall.sh” to update all of the projects and plugins.
IMPORTANT: Never manully add new things here. The only way to get new release is to sync with trunk.