added a judgment of whether environment can restore Object#prototype.
Merge pull request #74 from nazomikan/patch-1

added a judgment of whether environment can restore Object#prototype.
Skip prototype properties

To be a proper object-keys shim, it has to only iterate over own properties.

Would you be OK adding a dependency, `object-keys`? It's a well-tested Object.keys shim.
Merge pull request #76 from ljharb/patch-1

Skip prototype properties
First cleaned tests
dded that weird field
Adding one more test
Restructuring the stringify nit testsuite
Tests for nested
facepalm
Structure as Tests
Merge pull request #81 from sebs/master

Cleanup of the Tests