Python 3 fixes, simpler binmode initialization, high level I2C calls, and I2C EEPROM class

These commits contain various fixes for Python 3 compatibility as well as simpler binmode initialization (new configure method calls BBmode and enter_* correctly), high level I2C device_read and device_write calls, and a high level EEPROM driver with selectable address size.  All I2C device methods support switchable 7 bit or 8 bit addresses.  Also, some missing __init__.py files are included.