add support for new categories - for example flickering lights for epileptics

[nitsanWojakovsky]

Support additional categories and not only the current 4 (violence, verbal abuse, nudity, alcohol and drug consumption). This will expand our market and user's profile - by not only targeting people who wish to censor their movies from "bad" behaviours and actions and making our product relevant for health reasons ( for example the epileptic crowd ) and many more.

[ophirhan]

Defining new categories should be done in the CNSR file specification repository. As we add new categories to the specification we need to add support for them in the viewer.