Get polyscripter to build again (QFRead change)

Tutorial build also needs tweaks for remove-term-eqtype

Comments updated to reflect tautLib upgrade.

Summary: tautLib upgraded to use HolSatLib engine.

Details:
* tautLib signature (and behaviour hopefully!) is unchanged.
Internally, TAUT_CHECK_CONV now uses HolSatLib.
* HolSatLib can now handle Boolean-valued conditionals. This
was forced because tautLib handled them.
* We now have full drop-in support for zChaff, via a proof translator.
* HolSatLib now deletes temporary files.
* Legacy HolSatLib interface dropped in favour of simpler
interface with single entry-point, plus some convenience
wrappers.
* examples/miller/m renamed to selftest.exe; now works with build -selftest
* build-sequence changes: src/compute and src/HolSat/* moved above src/taut;
examples/miller stuff condensed into one entry
* build.sml patched to handle zChaff proof translator (in C++).
* New windows binaries for MiniSat and zChaff proof translator.
* Changes/additions to HolSatLib interface rippled to affected files.
* Documentation updated. In particular, HolSatLib section in Description
had to be almost completely rewritten.
* HOL builds to selftest level 1 on standard kernel, and level 2 on
experimental kernel. Level 2 failures on standard are non-critical
and authors have been informed.

Update dpll example with reference to HolSatLib's SAT_TAUT_PROVE function.
(The example in dpll.sml was also not the same as the one in the manual,
so fixed this too.)

Updated example code to correspond to what is in the Tutorial chapter on
proof tool construction.

More text describing the DPLL tool. Will update the number about how slow
the tautLib version is when it actually get rounds to finishing.
Also, source code for what's in the chapter.