Added picojpeg benchmark

    * configure: Regenerated
    * configure.ac: Added picojpeg benchmark
    * src/picojpeg/Makefile.am: Makefile.am for picojpeg
    * src/picojpeg/Makefile.in: Regenerated
    * src/picojpeg/picojpeg.c: Library file for picojpeg
    * src/picojpeg/picojpeg.h: Library file for picojpeg
    * src/picojpeg/picojpeg_test.c: Benchmark file for picojpeg