Configurable shakeIntensity

Hi,
I'm applying your project to mine, and I need to change shakeIntensity and size of particle of effect 2. (I wanted to lower these)
However, there aren't configurable options about these yet.
So I made some options for my use and if you are interested in, let me know. I'll open pull request.

You can find my works at [this compare](https://github.com/chinchang/code-blast-codemirror/compare/master...Jayde-Im:configurable-options) and I also updated demo, you can check how it works.

Any suggestions are welcome.

Thanks to your great work. :)
Jayde.