Add/Correct: FT2232H, ReadBytes, command in i2cget 

First of all I added the constant FTDI_DEV_ADDR which you can use to change the productId of the device, so it is possible to use an FT4232 (0x6011) or an FT2232 (0x6010).
Then I correct the patched function ReadBytes, which used the FTDI-function of manufactor (FT_...). 
In the function ReadByte (not in use now) there will send an NACK now to the device.
There were made different fixes in the processing of the arguments in the main function. There are now different values for the address for reading, writing and a command oder eeprom-address. If an address of the eeprom or an command is given, the program now "send" the eeprom address or command to the i2c device for reading the correct address, i2csend is not needed for setting the address now. If the new parameter  (-n) is given, the program reads the given number of bytes using the function ReadBytes.