Rename main branch to main?

[arbourd]

master has been replaced with main in most cases / repos. Although not required, perhaps this project should also consider abiding by that community change?

It should update open pull-requests.

[manast]

For new projects makes sense, but I wont spend time on a change that will not bring any value other than potentially break something for one or two users. I understand there are political issues behind things like this, but in my view there is no room for politics in a software project. Please respect my view on this.