More spec progress: - language for selectors and array/map indices - formal description of syntax notation used - factor out common productions to better show   symmetries in grammar
More spec progress:
- language for selectors and array/map indices
- formal description of syntax notation used
- factor out common productions to better show
  symmetries in grammar

R=r
DELTA=113  (77 added, 13 deleted, 23 changed)
OCL=16853
CL=16865

tav/go,tav/go,tav/go,tav/go,tav/go,tav/go,tav/go