Fix Test_issue80 on Go 1.8
Fix Test_issue80 on Go 1.8

An upstream change (http://golang.org/cl/30371) makes the Go encoder
to be more compliant with the ES6 standard. Ironically, this change
causes Test_issue80 to fail on the larger number ranges.

To make this test work on both Go 1.7 and Go 1.8, we delete the larger
value tests, which are arguably locking in the wrong behavior.

deoxxa/otto,kingland/otto,robertkrimen/otto,deoxxa/otto,emicklei/otto,kingland/otto,emicklei/otto,emicklei/otto,robertkrimen/otto