Reordered 1D

Reordered 1D Classic code from 4.6, with PyClaw 1D routines replacing the 4.6 ones where applicable, and common files copied over from 2D/3D.  The included example is a port of the book example chap9/acoustics/interface, and agrees with the results from that code.  May want to increase the precision of the output in out1.f later; it's only 8 digits right now, but I left it that way for the sake of agreeing with the older versions.