fix null pointer error
fixed bug where _internalObject wasn't getting cleared in dispose()
Overhauled add/edit data source panels.
ILinkableObjectEditor now has a function to check for pending changes.
DynamicColumnEditor now allows changing the active data source.
DynamicColumnEditor now refreshes active category when hierarchy
changes.
Numerous bug fixes related to GUI-linked objects becoming disposed.
UIUtils.pad() now does more useful stuff.
tooltip now shows immediately when f8 is pressed (identify)
fixed null pointer error
no longer rounding numbers to zero in equation display