Enhancements to QMB
    * added shift rotate buttons to model tuning section to allow for easier shifting of atomic model
    * added interactive view of currrent model zone axis
    * reorganized layout (with GUIDE) to make things a little cleaner
    * added graphical button labels for shift buttons, rather than simple text ones (purely an aesthetic change)

Squashed other commits into this one.
Merge pull request #34 from jat255/qmb_modifications

Qmb enhancements