Fix automatic semi-colon insertion

Fix automatic semi-colon insertion in var statements without
initialisers.
var i
i = 1;
is valid and not accepted by the parser

but
var i = 2
i = 3;
is valid and accepted by the parser, as it should be.

With this fix, both are accepted.
Merge pull request #155 from fpirsch/patch-3

Fix automatic semi-colon insertion