A function call as character to the specified function with corresponding package as attribute
Arguments
type
name of calculation/source
prefix
Type of calculations. Available options are "download" (source download),
"read" (source read), "correct" (source corrections), "convert" (source conversion to ISO countries),
"calc" (further calculations), and "full" (collections of calculations)
ignore
vector of arguments which should be ignored (not be part of the function call)
error_on_missing
boolean deciding whether a missing type should throw an error or return NULL