Improved the automation of scripts.

* [DCG_MULTI,FIX] dcg_multi1//5 would not adhere to the set range of repetitions.
* [DIR_EXT,NEW] Added wrapper create_project_subdirectory/2.
* [SCRIPT_STAGE,NEW] Rewrote this module, adding support for an input and output directory. Also added support for automatically ending and cleaning a script. Also added file search path abbreviations.
* [USER_INPUT,NEW] New module, based on a predicate from META_EXT. Adding DCGs fir file names, directory names and filepath names. Added predicates that ask the user to give a file or filepath. Added legal expression checking to user input. Added a generic method for arbitrary user input that is checked for legality.