Better formatting
added flag capabilities, rewrote error checking, ++

flags:
  >added flag "--all" to download to download all courses based on
subdirectory names
  >added flag "--organize" to download course videos into course
subdirectory. ###NOT YET IMPLEMENTED##

Error checking:
  >added error checking for existance of course, will no longer
terminate execution and blame username
  >fixed implementation of login checking

Added help documentation
Cleaned up implementation
added --mp4 flag and implemented --org functionality
added --help flag, created settings dictionary, cleaned up implementation