Refs #2514. Check parsed equations for compatibility with destination
column before loading. If incompatible, store as an ErrorEquation rather
than a regular Equation. Avoids potential exceptions thrown by
CyTableImpl that caused the table browser to malfunction.
Revert "Refs #2514 - resolves issue with Integer equations causing NPE"

This reverts commit bd5bdee2250430e082f98980828bd7778f57318d.

Commit not necessary to fix #2514, and could cause (potentially undesirable) changes to table behavior.