[auth] Use pyramid_multiauth
It makes it easier to finely tune what parts of the default authentication stack
we want to use or not.
It also makes it possible for any cube to add its own policy in addition to the
others.
Related to #4985962
7ffca3b439105a0bcca1a6fdf83710be3083a4b1 pyramid_cubicweb-version-0.1.0
7ffca3b439105a0bcca1a6fdf83710be3083a4b1 pyramid_cubicweb-debian-version-0.1.0-1
3d60138100d660e430e069c5d104ec927820d298 pyramid_cubicweb-version-0.1.0
3d60138100d660e430e069c5d104ec927820d298 pyramid_cubicweb-debian-version-0.1.0-1
9f3b9e610c3dde38a20586f217d033ed4a4e73ca pyramid_cubicweb-version-0.1.1
9f3b9e610c3dde38a20586f217d033ed4a4e73ca pyramid_cubicweb-debian-0.1.1-1
5eb4e27e9998fd3e0fc0e6e38ce996c5d6951be3 pyramid_cubicweb-version-0.1.2
5eb4e27e9998fd3e0fc0e6e38ce996c5d6951be3 pyramid_cubicweb-debian-version-0.1.2-1
0a7769e583c2499163cd3765a2a851b8a95011ec pyramid_cubicweb-debian-version-0.1.3-1
0a7769e583c2499163cd3765a2a851b8a95011ec pyramid_cubicweb-version-0.1.3
cd8308245d200092c228dbdd0fa8bcfec748c2fb pyramid_cubicweb-version-0.2.0
cd8308245d200092c228dbdd0fa8bcfec748c2fb pyramid_cubicweb-debian-version-0.2.0-1
1ae61c25299a6312acd09dc8d2f2c65e2e53f93b pyramid_cubicweb-version-0.2.1
1ae61c25299a6312acd09dc8d2f2c65e2e53f93b pyramid_cubicweb-debian-version-0.2.1-1