New const: mAX_Long_REG

bump:	uNFOLDING_USE_THRESHOLD  	to 8
	uNFOLDING_CON_DISCOUNT_WEIGHT  	to 3

The Great Multi-Parameter Type Classes Merge.

Notes from Simon (abridged):

* Multi-parameter type classes are fully implemented.
* Error messages from the type checker should be noticeably improved
* Warnings for unused bindings (-fwarn-unused-names)
* many other minor bug fixes.

Internally there are the following changes

* Removal of Haskell 1.2 compatibility.
* Dramatic clean-up of the PprStyle stuff.
* The type Type has been substantially changed.
* The dictionary for each class is represented by a new
  data type for that purpose, rather than by a tuple.

Default for uNFOLDING_KEENESS_FACTOR (2.0) added; uNFOLDING_OVERRIDE_THRESHOLD removed

Removed mIN_BIG_TUPLE_SIZE

Cross module worker-wrappers

Adding and removing files

SLPJ new renamer and lots more

SLPJ changes through 960604

Add SLPJ/WDP 1.3 changes through 960404

simonpj/sansom/partain/dnt 1.3 compiler stuff through 96/03/18

Initial revision