Change the button creation code to use an array*

- I feel like this is a slightly less inscrutable way of generating the button/hamburger markup
- Previously `settings.parentTag` was being closed with a hard coded `</a>`
  - I'm assuming this was generally never raised as an issue because most people are probably using anchor links as parent tags anyway
  - Failing to do so would possibly be cleaned up by jQuery's html creation code, but better to be sure


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*the author of this pull request fully acknowledges that this pull request may at first glance appear to be a coarse  waste of the Very Busy Original Author of the Plugin's time, and if so, apologises, and herein offers this photograph of a golden retriever swimming with a dolphin in the hope that this may offer an enjoyable diversion to the aforementioned and presumably Very Busy plugin author</sub>

![](http://31.media.tumblr.com/dc0e0d929ea0a5be5349130b00508479/tumblr_mqk32k2PaZ1sbmaxlo1_1280.jpg)