Add TOperandEdit class and operand adding & removing.

Add TOperandEdit class and operand adding & removing.

! Fix bug when edit box doesn't exist.
  [MemoryEditClass.pas]
* Add TOperandEdit class and operand adding & removing.
  [OperandEditClass.pas], [HardwareClass.pas], [MemoryViewClass.pas]
* Validate Instruction Name and Code on change.
  [SteppingClass.pas]
* Add descendant removing.
  [PrefixTreeClass.pas]
* Show type of operand in view.
  [MemoryViewClass.pas]
* Rename InstructionValidate to ValidateInstruction.
  [AsmGridClass.pas], [FPUFormClass.pas], [HardwareClass.pas]
* Change tabstop order and dialog layout.
  [AsmGridClass.pas]
* Refresh lines properly on construct time.
  [AsmGridClass.pas]
* Add constants & resources to support new functionality.
  [ConstantsClass.pas], [ResourcesClass.pas]
* Add OnOperand event handler.
  [CustomViewClass.pas]
* Rename HardwareState to Hardware.
  [HardwareClass.pas]