- rewrote section on numeric literals (grammar easier to read,

separate between ints and floats, added language regarding the
type of numeric literals)
- added language with respect to the scope of labels
- introduced ideal types for the purpose of the spec
- added language to expressions, operands
- added some more formal language about ideal type conversion
  (probably not 100% correct yet)

R=r
DELTA=145  (69 added, 4 deleted, 72 changed)
OCL=15165
CL=15186