testmfs, testisofs: MFS format, ISO functionality

testmfs: catch MFS format changes

This test tests mkfs.mfs will generate the same FS image given the same
input files. mkproto creates a proto file (normalizing directory entry
order). The assumption is that a change in the output flags a tacit
change in FS format, and that a FS format change will cause the image
to change.

        . Changes to mkfs.mfs that innocently change the format can
          change the sha1 output in the script along with it.
        . The assumption is that corresponding versions of mkfs.mfs and
          MFS will always work together; otherwise a lot breaks (ramdisk etc.)
        . Therefore, as long as a generated FS image stays the same with the
          same input now, incompatible MFS changes will still be flagged,
          even if they work together with the current mkfs.mfs.

testisofs: test ISO filesystem

        . to test isofs: prepare an ISO FS image using writeisofs, copy it
          to a RAM device, mount it using the iso9660fs server, compare the
          SHA1 contents of the files on the ISO with the inputs.
        . use su to run certain commands in the script as root

run script: run shell script tests

	. they are installed without .sh so should be
	  searched for as such
	. add diagnostic when tests are skipped

Change-Id: I30daff58e1e43903dacf3c99996a4a0e7d819b6b

test/Makefile

@@ -74,7 +74,7 @@ PROGS+= test${t}
 PROGS+=	t10a t11a t11b t40a t40b t40c t40d t40e t40f t60a t60b \
 	t67a t67b t68a t68b
 
-SCRIPTS+= run testinterp.sh testsh1.sh testsh2.sh
+SCRIPTS+= run testinterp.sh testsh1.sh testsh2.sh testmfs.sh testisofs.sh
 
 .if ${MKPIC} == "yes"
 # Build them as dynamic executables by default if shared libraries