This is not a stand-alone test.

erp5_data_notebook: If wrong setup method was added, then remove it otherwise jupyter becomes permanent unusable state.

erp5_data_notebook: Don't try to serialize well known unserializable objects and ignore any exceptions happened during serialization otherwise jupyter becomes permanent unusable state.

erp5_data_notebook: Support _repr_html_. Object such as pandas' DataFrame is rendered as HTML in Jupyter.

This reverts commit fc67555b.

zope.{interface,component} implement Interfaces through __implements__,
__implemented__ (both implementedBy instances) and __provides__ (ClassProvides
instance) attributes set on the class itself through implementedByFallback
(zope.interface.declarations).

However, this implementation creates circular references by referencing the
class itself and thus erp5.* classes (and all its Accessors instances) were
never GC even after a reset.

When running testXHTML and installing the Unit Tests bt5s:
  * After 10 resets:  21MB leak (~  7% of Zope process USS).
  * After 20 resets:  70MB leak (~ 18% of Zope process USS).
  * After 28 resets: 122MB leak (~ 26% of Zope process USS).

Fixes browsing ERP5 documents without activity tables available.
Of course, as most modifications trigger activity creation, no
modifications are possible. But this improves read-only access in
degraded conditions.
Also, by design a successful query must return one line, so do not test
returned value before processing it.

Allows recovering from broken connection strings, as ERP5 authentication
still relies on having a working catalog.

erp5_travel_expense: Record creation is eventless

erp5_travel_expense: Representative Record creation is done by an alarm