Regenerate figures as pdf.

modified:   ../ps2a/GNUmakefile
modified:   ../ps2a/partEcollectTimings.m
modified:   ../ps2a/partH.m
modified:   ../../METADATA
modified:   ../ps2b/GNUmakefile
modified:   ../ps2b/countItersAndPlot.m
new file:   ../ps2b/plotConvergence.m
modified:   ../ps2b/quadraticDifferences.m

use export_fig for ps2b.
regenerate ps3a figures.

modified:   ps3a/driver.m
modified:   ps3a/loglogExponential.m
modified:   ps3b/GNUmakefile
modified:   ps3b/PlotFreqResp.m
modified:   ps3b/displayOutputErrorAndCpuTimes.m
modified:   ps3b/plotFreqPartC.m
modified:   displayOutputErrorAndCpuTimes.m