A few minor refactorings of the proposed spec rules:
Change abstract syntax of memtype to have idxtype before limits (envisioning the general structure idxtype limits elemtype, e.g., should we once have Table64 as well).
Parameterise syntax of limits over index syntax to accommodate tabletype and mem-32.
Classify limits by index type instead of having an extra wrapper rule.
Added modified rule for memory type validation.
Factorise binary encoding for limits to make shared i64 memtypes expressible.
A few minor refactorings of the proposed spec rules:
idxtype limits elemtype, e.g., should we once have Table64 as well).