Add names for hash table types with the word `weak' in them.

Add names for hash table types with the word `weak' in them.

New global bindings:
  MAKE-WEAK-EQ-HASH-TABLE
  MAKE-WEAK-EQV-HASH-TABLE
  WEAK-EQ-HASH-TABLE-TYPE
  WEAK-EQV-HASH-TABLE-TYPE

{EQ,EQV}-HASH-TABLE-TYPE and MAKE-{EQ,EQV}-HASH-TABLE are now aliases
for WEAK-{EQ,EQV}-HASH-TABLE-TYPE and MAKE-WEAK-{EQ,EQV}-HASH-TABLE,
as are MAKE-{SYMBOL,OBJECT}-HASH-TABLE.