Add test for #77, integer overflow when parsing JSON scientific notation number.
Add test for #77, integer overflow when parsing JSON scientific notation number.

erickt/serde,tempbottle/serde,serde-rs/serde,3Hren/serde,eefriedman/serde,JohnHeitmann/serde,oli-obk/rust-serde,Hoverbear/serde,thorbenk/serde,Ticki/serde,csmulhern/serde,sidred10/serde,jmesmon/serde,skade/serde,pcwalton/serde,infinityb/serde