First of all, thnank you for taking the time to contribute.
Repository has master and develop branch. master branch is only for releases and commits to this branch are not allowed.
Before adding feature, create issue and describe it there. Everybody involve in this project should know about it.
General types of PRs are: feat, fix, chore, docs and name of PR should fit into this template <type>(<scope>): <description>. Example: feat(mail): Adds mail support.