Accept uint64 values for %d

[Kagami Hiiragi]

Hi.

Right now it's only possible to use ints with {%d … %} output tag, when I trying to pass uint64 I get the following error:

test.qtpl:8[/home/user/test.qtpl.go:49]: cannot use id (type uint64) as type int in argument to qw422016.N().D

Could you please add support for uint64 too? Thanks.