Basic pass at better JNum equality testing.
Basic pass at better JNum equality testing.

This commit adds a safe equals method to the JNum classes. It
currently avoids potential floating point problems by aggressively
using BigDecimal, unfortunately, and could stand with some
improvement. But this change is still a big improvement.

jedesah/Quasar,quasar-analytics/quasar,djspiewak/quasar,quasar-analytics/quasar,jedesah/Quasar,slamdata/quasar,quasar-analytics/quasar,drostron/quasar,drostron/quasar,quasar-analytics/quasar,jedesah/Quasar,drostron/quasar,slamdata/slamengine,drostron/quasar,slamdata/slamengine,jedesah/Quasar,slamdata/slamengine