This does not change the grammar. It merely updates some text in the comments,
which shows a rule that was changed at some point but its copy in the comments
was not properly updated.
Thanks to @bendyarm for noticing this.
Types are now required in variable and constant declarations (including for loop
variables), and for literals (i.e. there are no longer untyped literals).
This "merges" the two previous slightly different notions of array type
dimensions and array expression dimension(s) into one notion of array
dimensions, in which the dimensions have to be natural numbers. (Previously,
array type dimensions were allowed to be unspecified (via underscores), while
array expression dimensions had to be specified.)
