code: protected Boolean coerceToBoolean(Value value) {
  		if (!(value instanceof BooleanValue))
  			throw new CommandExecutionException("Value is not a boolean");
  		return ((BooleanValue) value).get();
  	}
docs: Coerces a value to Boolean. Throws a
  {@link com.github.srec.command.exception.CommandExecutionException} if
  value is not of the expected type.
  
  @param value
  The value
  @return The converted value