Log Message:
Update 1.9016 to 1.9021
-----------------------
1.9021 2014-07-17

 - Spelling fix in documentation.

1.9019 2013-10-01

 - Rename $b to $bits so that netmask can be sorted.  Change mostly
   from https://rt.cpan.org/Ticket/Display.html?id=76939

1.9018 2013-09-26

 - Minor MANIFEST fix.

1.9017 2013-09-20

 - Add network split() function.
 - Re-arrange the distribution a bit.