Print a usage message from embedded POD documentation
Description
pod2usage will use its embedded POD documentation to print a usage message
for the invoking script and then exit the script with the desired exit status.
The usage message printed may have any one of three levels of "verboseness":
If the verbose level is 0, then only a synopsis is printed. If the verbose level
is 1, then the synopsis is printed along with a description (if present) of
the command line options and arguments. If the verbose level is 2, then the
entire manual page is printed.
