Remove ugly chars from end with regex

I noticed in the demo (http://micjamking.github.io/succinct/) that if you use the character count as _30_ it leaves a "," at the end. this bothered me so i made a really simple addition that matches a regex at the end and removes characters like: 

*,.{[(<¦¬~^

this is set as an option so the user can change, remove or whatever. if set to 'false' it wont try to remove.
Revised ignore patterns
Revised special character check
Merge pull request #4 from micjamking/uglychars

Revised special character pull request