Added some more diagrams and pictures

	new file:   exp4/report/diag/meas_pressure.pdf
	renamed:    exp4/report/img/IMG_20130321_153035.jpg -> exp4/report/img/airfoil.jpg
	renamed:    exp4/report/img/IMG_20130321_123242.jpg -> exp4/report/img/balance.jpg
	renamed:    exp4/report/img/IMG_20130321_123221.jpg -> exp4/report/img/manometer.jpg
	renamed:    exp4/report/img/IMG_20130321_123136.jpg -> exp4/report/img/weights.jpg
	modified:   exp4/report/report4.tex