fix #1033 Removing wrong lines in the MultiAutoComplete.

This commit removes two lines which set a new value in
the data model when pressing tab if the field is empty
and not positioned at the end of the options (i.e. when
leaving the edit mode through tab if the field is empty).

There is no reason to set the value at that time as the
value has not changed, and this can lead to the onchange
handler being called later when the value has not changed.
fix #1038 Updating skin property for MultiAutoComplete widget

This commit updates the multiautocomplete property for skins.
fix #1032 viewport sizes updated when the first autoresizable element is registered
viewport sizes are now also updated when the first autoresizable element is registered, and not only when Layout singleton is loaded or a resize is done.
fix #1048 jshint es3 parameter set to true (old browsers support)
feat #1040 Check the skin when normalizing it

This commit updates the version of atpackager, and updates
the configuration of the ATNormalizeSkin visitor to check
the skin properties while normalizing them. In case a skin
property is not correct (i.e. if it does not match the
corresponding bean in aria.widgets.AriaSkinBeans), the
build fails.

Close #1040
fix #1041 MultAutoComplete changes when suggestion is under edit mode
adds support for Greenlandic language

Closes #1050
fix #1052 headers were declared as Object in bean

`headers` entry in request beans was declared as Object and not Map, which
meant that JsonValidator would fail when validating any non-empty
`headers` taking the RequestBeans cfg.

For consistency, `headers` are changed to `json:Map` in both related
places in CfgBeans and RequestBeans.
POST requests headers transmitted when using XDR
feat #1044 add aria.core.IO.postHeaders

This commit adds `aria.core.IO.postHeaders` array in order to add more
flexibility to the users and facilitate code simplification in 1.6.1.

It also properly deprecates certain features intially deprecated in 1.2.6
and 1.3.1 by improving documentation and adding deprecation warnings.

The code has been also slightly refactored to facilitate removal of
deprecated items in 1.6.1.

---

To sum up the situation, the following config options are deprecated:

In aria.core.IO:
- `useXHRHeader` and `defaultXHRHeader` (use `headers` and `postHeaders`)
- `defaultPostHeader`, `useDefaultPostHeader`, `defaultContentTypeHeader`,
   `useDefaultContentTypeHeader` (use `headers` and `postHeaders`)

In aria.modules.RequestBeans:RequestObject:
- `postHeader` (use `headers`)

In aria.core.CfgBeans:IOAsyncRequestCfg:
- `postHeader`, `contentTypeHeader` (use `headers`)

Close #1044.
adds short day strings for Chinese

Closes #1059