Can it be an open source project? #25

Searching through the repository I cannot find any mention to open source licence. By this project being on Github, I am allowed to fork it by the Github TOS (Terms Of Service). However I am not allowed to create derivative works from it (pull requests). Meaning I cannot fork this repository, change its code and perform pull requests without the danger/liability of being prosecuted by violating the All rights reserved copyright granted by berne convention law.

Related issues:

1. Can it be an open source project?  gamcoh/QuickEdit#2 Can it be an open source project?
2. Can it be an open source project? LaTeXTools#1175 Can it be an open source project?