EBNF definition of Positive Integer Literal allows (infinite) zero padding

[DavidUnderdown]

as the definition is PositiveIntegerLiteral ::= [0-9]+ /* xgc:regular-expression */ this allows integers to have an (infinite) number of leading zeroes. Typically when we say that it should be a PositiveIntegerLiteral we are anticipating that there would not be leading zeroes. For 1.2 it would be good to revisit this.