added default value for last_active_snap_point
fixed division by zero issue
removed old comment
ignore sp outside the viewport in 'oaadd-modal' and in order_sp_list
more pythonic way to calculate the hue for the snap points
fixed bug: crash when sp is outside of viewport at the same oa-obj
new feature: show all snap points
show snap points index
minor optimization
added gl_free when the oa-mode-operator gets cancelled
changed label of enter-oa-mode-operator, some layout reorganization and new icons
new feature: replace model(s) with other model (with best-matching variation)
skip the search for a best match when only one variation is available