[manage view] cleanup manage view and user menu * drop code that shouldn't be there (e.g. folders handling) * add a section displaying site management actions, some of them were initially in the user's drop down menu, which now only have a 'manage' link with regards to management actions * stop displaying 'system' and 'schema' entities by default, only 'application' entities * put 'gc', 'registry' and 'info' views as tabs of a generic 'server information' view

# type attribute might already be there if migrating from
# version < 3.5 to version >= 3.5.3, BaseTransition being added
# in bootstrap_migration
if versions_map['cubicweb'][0] >= (3, 5, 0):
    add_attribute('BaseTransition', 'type')
    sync_schema_props_perms('state_of')
    sync_schema_props_perms('transition_of')