Fixed: Mistakenly added .c file to list of .o files
Changed include file and compiler flag

- Changed from including '<unistd.h>' to '<getopt.h>'
- Changed compiler flag from '-std=gnu99' to '-std=c99' made possible
  due to include change
Added '-ansi' flag to Makefile and relevant C code changes

Added the '-ansi' Makefile flag caused a few code changes:
- Starting comments with '//' had to be changed to '/* ... */'
- Mixing variable declararions and code not allowed in ansi C