Added additional XOR gate to the WWAN page. This makes it possible that the polarity of the SIM_DETECT signal is configurable by one single O-Ohm-resistor.
This adds more flexibility concerning modem choice, as there are both polarities of this signal used by different modem manufacturers.
Added placeholder symbol for modem card (which holds now datasheet/bom information). The MPCIE socket has datasheet information, too.
Picked two electrolytic capacitors (220uF/10V) by Panasonic by distributor TME.