Fix src/real for tight equality

Bulk of changes just set grammars back to loose equality for script
duration.

Remove unnecessary structure bracketting

As per 89fc99bc3, but on as many examples as a grep -R can find.

trailing newlines in *.{sml,sig} files from src/ removed

Trailing newlines from SML files in src/ were rendered in HTML documentation.

Finally got around to fleshing out the real simpset (the other changes are
the ramifications of this!)

Major changes:

1. Got rid of AC rewrites for + and *. If you want them (perhaps for
compatibility with the old real_ss), use real_ac_ss.

2. Added a huge bunch of useful rewrites to real_ss, though I'm sure
I'll need to add a huge bunch more before I'm finished with it.

Removed gratuitous incompatibility with Taupo-6 in type of set_fixity;
its type is now string -> fixity -> unit, rather than
(string * fixity) -> unit.

Changing arithLib to numLib. And RealSS to realSimps.

Not sure ...

The reals library builds on Kan.0.

Now that overload_on alters the order in which resolution of ambiguous
parses is done, the calls to overload_on that repeated overloading
information for the natural number operations actually messed up
subsequent parses. We know that the calls were redundant because the
polyTheory is built on top of realTheory, which must have already set
up overloading for reals and nums.

In polyScript, the polynomial operators have been overloaded. We are
not sure whether this is a good idea or not.

Changes due to the incorporation of John Harrison's datatype definition
package.
Many of these due to the fact that `n:num + b` parses differently because
sumTheory is now in the ancestry. A couple of other changes due to
explicit references one or two proofs made to num_Axiom. These are now
to num_Axiom_old.

Fix to make it build now that = is non-associative.

Minor changes to use "jrhUtils" instead of "useful".

Upgraded to use overloading.

Fixed to bring it up to date with Taupo release 0.
(Changes have come across from parse_branch development.)

Initial revision