Adds coment explaining the problem

Modified layout of re-racking page

Changed start racking button to open rack layout panel

Refactored re-racking model

Split re-racking model into a few extra methods.
Changed Re-Rack Tubes to Save Tubes
Will now validate file before doing anything else.
Changed when panels collapse to hoepfully make things clearer
Merge pull request #453 from jbeast/re-racking-print-label-last-fix

Re-racking print label last fix