This assignment covers file I/O. Must design and code a program
that can accomplish four things: copy one file to another (i.e.,
place the contents of file A into file B), ‘compress’ a file by
removing all vowels (a, e, i, o, u, and y) from the file, merge two
files, and finally double each line of an input file, saving into
an output file. Also make it so the input file's content can be
changed from the example given....