added int fileDescriptor to Communications.h (necessary to work with file) and function to scan a * and return the file (this is mainly for convenience, as the device number is constantly changing).
Example:
	Serial.begin("/dev/ACM*", 9600);
Will look for the first ACM it finds, so that if it changes we don't have to keep changing the command.
NOT IDEAL FOR MULTIPLE DEVICES (who knows what will happen)