Linkable double spool system (Q44967)

This is a derivative of: http://www.thingiverse.com/thing:4337 by randyy There were several things I didn't like about this. The first is the spool was too small, so my filament would just unwind itself. The second was that I didn't have any rods to go between the spools. Finally, the hole in the middle was too small for the rod I wanted to but it on. So what did I do? Made it extend-able, so the size of the spool can be changed. Made the center hole bigger. Made it so I could attached printable hooks to hold the plastic onto the spool (and made them double, so that it would hold more plastic!) AND, to save myself some plastic, I made the ends with connectors so you can attach them and hopefully get more plastic onto less spools.