LogicLevel: Added toLogicLevel()
FlipFlopJK: Finished code, added test.
ToolTraceDrawer: Testing some overlap drawing
SpatialGrid: Now reserves exact size on construction
EditorPanel: Fixed bad graphics generation on demo demux
Merge branch 'SimulationDev' into EditorPanelDev
Added TestCounter class: simulates a 4-bit counter with JK flip-flops
FlipFlopJK: Fixed potential bug with hold mode
LogicLevel: Fixed isEdgePos() not being static
PinIo: Expanded interface in preparation for code deduplication
Component: Must now implement reset()
ComponentActive: Updated with new PinIo interface.  Now responsible for
creating IO pins, removing the need for redundant code.  Also added
isCombinational() informational function.
Component: comments
ComponentPassive: Deduped, now has defaults for Stateful interface
Decoder: Refactored, deduped
Display: Deduplicated code
DisplayLed: Refactored and deduped
DisplaySevenSeg: Refactored
TestHalfAdder: Updated methods to match new stuff
GateNand: Now overrides evaluate instead of update(). Refactor + dedupe