Fix state name cannot contains underscore issue

[fengye]

Thank you for creating the plugin. It works well.
I find the state name cannot contain underscores, otherwise the corresponding state-based function not get called, such as void MY_STATE_IDLE_FixedUpdate(). So I made some changes in the function-finding part, and it now splits the function name with the last underscore it finds.

[thefuntastic]

Oh wow, this is from a million years ago, sorry I'm normally good with responding but I see from the timestamp things were crazy at that time. Looks like I good commit. There is a potentially for a Array out of index error though.

Will try incorporate this feature next time I'm working on the project