jQuery noConflict() mode fix

[jontas]

trafficstars

As I mentioned in the github issue I opened on your project (https://github.com/sophilabs/jquery-counter/issues/8), this pull request fixes the problem when using jQuery's noConflict mode.

I also created a new file (examples/simple-noconflict.html) showing the plugin working in noConflict mode.

[cmfcmf]

Thank you, that solves it! I hope this get merged by @sophilabs :+1:

[kontur]

Looks good and makes the plugin usable in situations with other frameworks - should get merged.