Don't rollback if exception is HTTPSuccessful or HTTPRedirection
In the request finishing, the 'cleanup' callback set by _cw_cnx
automatically commit the transaction except is an exception is set
on the request.
Problem is, redirections and successul http return code can raise
exceptions.
This patch detects such exceptions and avoid rolling back the transaction.
Closes #4566482
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