Added PredicateIndicator struct for indexing
PredicateIndicator now used for DB indexing
Added Prolog style checker (i.e. link)

Checks for undefined/unused predicates, etc.
Prolog checker now walks higher order primitives

So if a predicate is only used from within a call to findall, the
checker won’t think it’s unused.
Checker walks heads of rules for higher order predicates

So if a predicate is only referenced in the head of a rule for another
predicate that’s higher-order, it will get noticed.
Implemented prematching of Prolog rules

Does a quick deterministic prescan of all arguments to the rule before
trying a real match.  This detects obvious matching failures without
allocating any memory (iterators, logic variables, structures).
Optimized matching of PredicateArgumentIndexers
Changing KB in Repl now changes it in ELInspector
Fixed bugs with locomotion control
Lowered animation quality (reduces CPU use under parallels)
Characters now have different sprite sheets
Added events.prolog for future use
Added decls to eliminate warnings
Fixed bug with busy-waiting in conversation

Constantly issued stop command.