Forward events when creating a new poly. Add unit tests

[volodymyrrudyi]

This is a possible solution to an issue described in #242

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[volodymyrrudyi]

Hey guys,

I've just signed it,

Have a nice day

On Tue, Jan 5, 2016 at 9:13 PM, googlebot notifications@github.com wrote:

Thanks for your pull request. It looks like this may be your first
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#247 (comment)
.

Regards,
Volodymyr

[googlebot]

CLAs look good, thanks!

[volodymyrrudyi]

Recreated from another branch in #248.