added cygwin build instructions (thx Smx):   README.md
	builds for both linux and cygwin:   build.sh
	renamed:    src/lz4/bench.h -> include/lz4/bench.h
	renamed:    src/lz4/lz4.h -> include/lz4/lz4.h
	renamed:    src/lz4/lz4hc.h -> include/lz4/lz4hc.h
	new file:   include/squashfs/7zDecode.h
	new file:   include/squashfs/7zExtract.h
	new file:   include/squashfs/7zHeader.h
	new file:   include/squashfs/7zIn.h
	new file:   include/squashfs/7zItem.h
	new file:   include/squashfs/Lzma86Dec.h
	new file:   include/squashfs/Lzma86Enc.h
	new file:   include/squashfs/lzma_xz_options.h
	modified:   include/squashfs/unsquashfs.h
	fixing memleaks:   src/epk2.c
	deleted:    src/lz4/Makefile.lz4
	modified:   src/main.c
	cygwin support:   src/squashfs/mksquashfs.c
	cygwin support:   src/squashfs/unsquashfs.c