Removed two figures and references

Removed:
old figure 4:  Distributions of commute trip length in 10-mile
intervals by a) income class segment, and b) car ownership segment,
(pre-earthquake)
old figure 8: One-way commute trip information by (a) 15-minute time
interval, and (b) 10-mile distance interval for 3 case study TAZs and
the average over all TAZs.

Also, fixed a reference issue in section 3.1