graphguide/ch2_concepts.py: fix saveToFile-->drawToFile
graphguide/ch2_concepts.py: fix saveToFile-->drawToFile

kanarelo/reportlab,Distrotech/reportlab,kanarelo/reportlab,kanarelo/reportlab,Distrotech/reportlab,Distrotech/reportlab,Distrotech/reportlab,kanarelo/reportlab,kanarelo/reportlab,Distrotech/reportlab