[ADD] ws doc: introspection, reports and workflows

* use static imports in java examples to make them terser
* inline ``domain`` in java and php example to make examples more
  self-contained
* try to extend/improve Model.write's docstring
* add convenience kwarg to fields_get, mostly for user-driven
  introspection

Closes #3689
[CHG] doc: company officially renamed
[FIX] yet another filter fix... (crm reporting)

Same problem as before: filters do not compose properly with the implicit
'&', and they are filtering on the wrong model (should filter on probability
in the crm.case.stage model and not on the crm.opportunity.report)
[FIX] doc/backend: typos in example code
[FIX] im_chat: unlink im chat presence on user deletion

It wasn't possible to delete a user if he had a im chat presence linked to him.
[REF] mail: extract auto subscribe notifications sending into a sub-method

To allow customization, such as do not send the notification to the partner that subscribed himself to the thread (he probably already read the thread, no need to send him an email)
[IMP] http: do not log traceback for Warnings
[IMP] Show product_uom_qty instead of normalized quantity in mrp order report
[FIX] mail: allow to set own batch size for mass mailing
[FIX] mail: batch_size expects an integer
[IMP] account : Add reference field to Invoice report
[FIX] product_extended: price from bom is build for product templates

As it sets the standard_price field, which is defined on product templates only: setting the standard price of a product variant will lead to set the standard price to all the variants of the product template.

There is therefore no meaning to compute and set the standard price of product variants according to the boms
Revert "[FIX] stock_picking_wave: removed obsolete many2many widget from stock_picking_wave_view"

This reverts commit 436bbb0a48ff866925fe0a3987928ab554bc3c6d.

The many2many widget is usefull, as it allows to select an existing picking instead of creating a new one when clicking add an item from the list
[DOC] web: search view: extra info about key events handling

Complements bde1a4432fef4cb2f5fe8ab600e72ab5b8b4830d