[IMPROVEMENT] Add LICENSE File

[thealphadollar]

Please prefix your pull request with one of the following: [FEATURE] [FIX] [IMPROVEMENT].

In raising this pull request, I confirm the following (please check boxes):

• I have read and understood the contributors guide.
• I have checked that another pull request for this purpose does not exist.
• I have considered, and confirmed that this submission will be valuable to others.
• I accept that this submission may not be used, and the pull request closed at the will of the maintainer.
• I give this submission freely, and claim no ownership to its content.

My familiarity with the project is as follows (check one):

• I have never used CCExtractor.
• I have used CCExtractor just a couple of times.
• I absolutely love CCExtractor, but have not contributed previously.
• I am an active contributor to CCExtractor.

---

We should be adding a LICENSE File to the root of the project. We do mention that we follow GPL v2 and hence can include it's declaration file.