feat #911 Form serialization method

A new method is available in singleton aria.utils.Html. It allows to serialize forms in order to use standard ajax calls to submit them.

Close #911.
fix #864 remove DPI test from css.Units constructor

This commit also adds an additional check for a related error when
the developer is calling `preloadSkinImages` from <HEAD>.

Close #909.
fix #917 Remove unnecessary body focus in aria.templates.TemplateCtxt.$focus

This one broke test.aria.templates.keyboardNavigation.TableNavTestCase on IE <= 8
doc #923 Improvement in the sorting method documentation for the LCReourcesHandler
fix #897 test.aria.utils.Html test fixed in IE7

Close #563. Close #569. Close #912.
fix #926 - blur not triggered in multiselect for IE

a click in a text input does not trigger the
blur event on the previously selected multiselect input, so
that the activeElement does not change properly
fix #833 Widgets cursor position is incorrect
feat #102 add `timeout` for `RequestMgr.sendJsonRequest`/`submitJsonRequest`

It's been always possible to pass a `timeout` to the calls of
    `aria.core.IO.asyncRequest`
    `aria.core.IO.asyncFormSubmit`
but not to the calls of
    `aria.modules.RequestMgr.submitJsonRequest`
    `aria.modules.RequestMgr.sendJsonRequest`

The latter only had the `aria.core.IO.defaultTimeout` applied.

This commit makes it possible to pass `timeout` as the key of the request
parameter object (first parameter) of them.

Close #102. Close #913.
fix #929 Incorrect short weekdays in Thai language

Short weekdays names were not correct in the date resources for Thai language.
doc Update README
fix #641 Possibility to package page engine resources

This commit introduces the possibility to retrieve site configuration and page definitions from a bundle.
fix #934 Missing and duplicate tests in the suite
fix #858 bump dependencies

Sorted them alphabetically by the way. Minor code fixes done for new
versions of JSHint and Jade.

Close #916.
feat #935 Addition of resources for Estonian language

Close #935
doc Incorrect sample in bean definition for IOAsyncRequestCfg

headers property in aria.core.CfgBeans:IOAsyncRequestCfg had an incorrect sample.

Close #938
fix #939 Overlay behaviour when body is scrollable

Loading indicators associated to an element are supposed to be cover and be cenetered only in the visible portion of the element.
This worked correctly apart from the case in which the body of the document has scrollbars. In that case, the overlay was not constrained to the viewport.

This commit fixes the issue by always constraining the overley in the viewport.

Furthermore, two other issues have been tackled by this commit:

* loading indicators were not being refreshed on window resize
* The message displayed underneath the spinner could end up outside the element, or was simply mispositioned in early versions of IE.
fix #936 Cross icon is no longer displayed for input widgets
fix #933 mispositioned labels in TextArea in IE7

This commit fixes the display:inline-block bug in IE7 that is affecting the label position for the TextArea widget.
feat #921 aria:List widget refresh on datamodel change

Now when you use aria.utils.Json.add and aria.utils.Json.removeAt functions to add items to an aria:List widget (or to remove one), the list template is refreshed and it displays the new item.
doc Improve Aria.load method documentation

Close #943