fixed path issue in plugin

[aakashtushar]

Fixed path issue in example file.

[artfuldodger]

Won't these changes break the instructions for running the example? The goal of the example is to be able to see it running locally without having to make any changes to code.

cd tinymce_equation_editor
python -m SimpleHTTPServer
# open http://localhost:8000/example/example.html

[aakashtushar]

I thought this example was instruction to setup the plugin. I was thinking it would be easier for users if they could just download the plugin, drop the plugin in tinymce's plugin directory, load the plugin name in tinymce init and run it smoothly. I had to make those changes (like in the example) in the plugin to make it work perfectly.