deleted comment-out code (calls to pstracker and showps); removed FIXME (is now fixed inside map_bird_ppi.pro)
moved a currently unused file to a separate new directory 'broken'
commented out a warning about atan2
added the environment variable IDL_ENRAM_VISUALIZATION_OUTPUT to the psfile url
added a common block
removed the common block (is now in its parent), and added the IDL_ENRAM_VISUALIZATION_OUTPUT dir to the psfile url