repo v2.31

1. acf63b2 drop pyversion & is_python3 checking by Mike Frysinger · 5 years ago
2. 784ccfc strip python2-only coding:utf-8 & print_function settings by Mike Frysinger · 3 years, 9 months ago
3. 7f7acfe Concentrate the RepoHook knowledge in the RepoHook class by Remy Bohmer · 4 years, 2 months ago
4. 16c1328 Move RepoHook class from project.py file to dedicated file by Remy Bohmer · 4 years ago