amend df name to reflect output of clean.r
ignore the PDFs generated by make
Start getting around circular dependency: create list of analysis files
Set dependencies separately for each key file so that analysis fiels can only be compiled after all key files are compiled.
Change the approach to creating dependency: every .Rout file depends on it's .R file and the recipe for this is R CMD BATCH $<. Then make a separate list of dependency rules for the 'key' files: clean.Rout depends on load.Rout etc