Entirely make cronscript magic

Entirely make cronscript magic

There is no longer a defined list of arguments it can handle.
Instead the arguments are defined in the var file, whose location
defaults to the FTPMaster location - but can be overriden using an
environment variable.

To be able to have specific types of cronscripts run pre/post actions,
we now check for the existance of preconscript and postcronscript
functions, and if they exist, they are run as the first/last thing
before/after anything listed in the .task file