Request permission to read organisation by default
Remove unused function
Fix some bugs in how oauth plugin handles URLs

There were several bugs that are fixed:
1) If page contains frames, they won't display correctly (cookies should be setted before redirection, not everytime)
2) There was a cyclic redirect if person is not in any allowed organisations

Maybe I'm missing something that's fixed by this commit
Add missing ltn12 require

It was used, but not imported
Encrypt AccessToken and Authorized cookie with aes128

Make everything a bit more secure
Use resty.core to speed up all the things a bit

It's faster with luajit + rest.core
Move config to a different file

It should improve usability