JPEG for euslisp

1. make libjpeg.so and put it in /usr/local/lib
   The default Makefile of jpeg-6a is organized to just produce libjpeg.a.
   You must add -shared, -KPIC, -Kpic, -G, etc., depending on the machine
   architecture.
2. make jpegmemcd.so using the makefile or makefile.linux in this directory.
   This is an addition to the libjpeg.so that enables in-core compression/
   decompression.
3. Load eusjpeg.l from euslisp. 
