Added PATH, ADDPATH and FILEPATH
Created COPYFILE, RENAME, FILES, DIRP, FILEP
Reimplemented FILEPATH with functions that can be later be reused
Implementation of OPEN-READ, OPEN-WRITE, OPEN-APPEND, READING, WRITING, READING-STRING
Implemented READ8, WRITE8, FSIZE, FLUSH
Removed debug statement.
Added ERROR, ERRORF, PAUSE.
Implemented DEBUG and TRACE-HOOK
Implemented NODEBUG
Added placeholders for ON-BREAK*, ON-INTERRUPT*. Implemented a trivial ERRNAME
Implemented string reader
Removed debug statement.