Add cproto-4.7f. TODO: integrate into pkgsrc compiler infrastructure?

Add cproto-4.7f.  TODO: integrate into pkgsrc compiler infrastructure?

Cproto is a program that generates function prototypes and variable
declarations from C source code.  It can also convert function definitions
between the old style and the ANSI C style.  This conversion overwrites the
original files, so make a backup copy of your files in case something goes
wrong.

The program isn't confused by complex function definitions as much as other
prototype generators because it uses a yacc generated parser.  By ignoring all
the input between braces, I avoided implementing the entire C language grammar.