Fix ReplicateStorage to reduce conflicts during synchronisation.

Creation and modification process now use the same code

/reviewed-on nexedi/jio!29

/reviewed-on nexedi/jio!28

Do not display error in browser not implementing WebSQL.
WebSQLStorage will raise an error is used in such browsers.

JSON.stringify is not stable by design and can not be used to generate the hash.
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/JSON/stringify

This commit adds a stable version of JSON.stringify, available at jIO.util.stringify.
Relying on the nearly same string representation will simplify compatibility.

Tests were failing because some Firefox versions cannot
parse a specific date-string. So the Date constructor
that receives only integers was used. But there is one
details: this contructor uses months from 0 to 11, so if,
for example, we want to have a date in January, we send 0
as month and not 1.

Fix ERP5Storage to reduce conflicts during synchronisation.
ERP5Storage.get return a new parent_relative_url property which will lead to changes from ReplicateStorage point of view.

Fix QueryStorage/MemoryStorage bugs.

Copy all documents/attachments set in the storage, to prevent unwanting external modifications

This ensure that document created during synchro contains the same properties on local and remote storage.

portal_type attribute is not set anymore on getAttachment('person_module', 'view') json.
This remove duplicated code.

All time objects now are handled as local time, doesn’t the test runner
timezone. Also all queries tests that once used the native Date are now
using JIODate.

Webkit has issues when trying to load data-uri based images with
XMLHTTPRequest this is changed for the sake of compatibility with all
browsers.

Contains an ERPStorage fix.

Put action is not send anymore by ERP5 if document is not editable.
See: nexedi/erp5@c71cfd66

Include support for ERP5 FileField

Include query parser fixes.

http://zaach.github.io/jison/about/

Jison is maintained and used by other JS projects (like Coffeescript)

Include WebSQLStorage.
New authentication for DavStorage.

This option is false by default to prevent any Cross Origin issue unsupported by most webdav servers

Squashed commit of the following:

commit 1591f5e199f91abca92ba3bb46ee3aa356c976fc
Author: Romain Courteaud <romain@nexedi.com>
Date:   Fri Dec 18 15:56:42 2015 +0100

    DavStorage: rename _withcredentials parameter to with_credentials

    Add tests.
    Update documentation.

commit 33b2113ca5ac42b015264f12776326d848320022
Author: Isabelle Vallet <isabelle.vallet@nexedi.com>
Date:   Wed Dec 16 06:22:08 2015 -0800

    DAV storage: add option for cross-origin cookie propagation.