Shared parts speed up compilation time and is becoming the standard in
SlapOS software installations, so it makes sense to use it in our test
nodes, as it also gives one more opportunity to test this feature.

erp5testnode configuration file supports a new shared_part_list option,
that can be set to a \n separated list of paths to use for shared parts,
following the same rules as slapos.core and slapos.recipe.cmmi (ie. the
first ones are read-only and the last one is read-write).

This shared_part_list option will be set in slapos.cfg used to compile
both the "software for testnode" (ie. selenium-runner) and later the
softwares under tests.
The software under tests will also use a local directory for each test
suite to install shared suite.

The directory structure is now:

  srv/
    shared/
      (shared parts to install selenium runner)
    slapos/
      soft/
        (selenium-runner software)
    testnode/
      foo/ # test suite with reference foo
        inst/
          (partitions of tested software)
        shared/
          (shared parts to install tested software)
        soft/
          (tested software)

and in the configuration srv/shared will be set as initial
shared_part_list.

When installing selenium-runner, srv/shared/ is used to write shared
parts. These shared parts are never removed.

When installing software under test, srv/shared/ and
srv/testnode/foo/shared/ are used. If parts are found in srv/shared they
are used, if they are not found, they are installed in
srv/testnode/foo/shared/.

In practice, this should mean that the shared parts installed by
selenium-runner will be reused for all tested softwares and this should
speed up initial installation of these softwares.

Currently, nothing is implemented regarding removal of unused shared
parts, but in our case:
 - srv/testnode/foo/shared/ will be removed when "foo" is removed.
 - srv/shared/ should be used only when installing selenium-runner.

If this starts to use too much disk space, one quick and dirty
workaround could be to destroy the test node instance and re-create it.

Before this change, class hierarchy is like this when using mixin:
```
class MyClass(BaseClass, Mixin1....)
```
which is usually ok when classes don't override each other's

But if we want to overwrite BaseClass's method by using mixin to do more thing,

For example:
```
class BaseClass(object):
  def test(self):
    print 'base test'

class Mixin1(object):
  def test(self):
    super(Mixin,self).test()
    print 'mixin'
```
I want to display 'mixin base test' when call test, but it doesn't work

since priority of how methods are resolved is from left

to right: BaseClass----->Mixin1, it only display 'base test'

So the correct way to use mixin should be in reverse order:
```
class MyClass(Mixin1, BaseClass)
```

/reviewed-on !935

When other nodes takes time to start they are not always registered
when the "main" node asserts that they are there.
We observed problems in an environment where resolving localhost (by
DNS) takes 10 seconds.

Also introduce getOtherZopeNodeList utility method that can be useful in
other ZEO tests in ProcessingNodeTestCase

When other zope nodes takes time to start this sometimes causes
conflict.

Reset mailhost before each test.

Commit changes created by portal_transforms.

This allows restoring the correct skin selection in ERP5JS.
Deferred reports can now be used in ERP5JS.

REQUEST is used to support direct form rendering, like: ./Base_viewHistory?deferred_portal_skin=ODS&portal_skin=Deferred

Thanks to Georgios Dagkakis for his work on this topic.
See !702

otherwise it loses too much precision.

Allow to sync opml event when some password are missing or broken (will only display public informations)

When adding opml from SlapOS interface, sync then show promise status.

Show Ressource consumption graph into separated graphs. Auto update of graph content is disabled by default, a new option is added to enable if needed.

Fix changes after merge with erp5 master which contains latests changes on renderjs

Intead of using opml software type, Hosting Subscription has now his own software type which simplify management.

[erp5_web_monitoring] increase opml import limit, show state of imported Instance and if they are monitored or not

[erp5_web_monitoring] Fix concurence problem on destroy OPML while sync is running or start just after

If Sync start in background and destroy OPML is launched, some data can be removed while sync is writing. So we prevent sync to run if destroy OPML is running and also, we refuse to destroy OPML if sync is running.

If the search result is only one item, redirect to the item view page, else redirect to the list of that items and let user choose the good one.

Monitor Jio storage has been updated to fix monitoring global Json files and set correct portal_type to it. The fix allow to keep backward compatibility with old/non updated monitoring backend instance.

This reverts commit ec926ea5.

This commit is still experimental, it was not supposed to be part of
this push.

This breaks matrix index consistency.
Also, call isBasePricePerSlice rather than introspecting wrapped method
arguments - the only wrapped method is _setBasePricePerSlice anyway !
Also, trigger SupplyCell_updateSliceBasePrice as it depends on
isBasePricePerSlice value on this line, and it just changed, and that
workflow does not trigger on line changes (which is a bug).
Also, get rid of a trivial local variable.

Rather than deleting them to just immediately create new ones with the
same ids but different uids.
Also, modernise code and follow naming conventions and coding style.