Fixed [1.3.0] option_plusone_explain outdated URL

[soloarquitectura]

http://www.google.com/+1/button/ redirects to http://www.google.com/+/learnmore/+1/

 

[Mike]

I guess it should be https://developers.google.com/+/web/+1button/.

 

[soloarquitectura]

Yes, I agree.