feat #788 Adding support for absolute URIs in the skin

Adding the possibility to pass an SVG directly as a data URI
inside the skin (and more generally to have absolute URIs
starting with http: or https: or data:).

Close #788
feat #782 Making text-decoration property of Link Widget customizable

Adding the possibility to customize the text-decoration property of Link widget

Close #782
fix #777 Dispose of templates in the page engine.

Close #778
fix #746 non existent skinClass configured for a widget now defaults correctly to 'std'

If a specified skinClass for a widget does not exist the 'std' skinObject is used (as before) and the skinClass 'std' is used for the naming of the css class names

Close #776
feat #787 Updating the List widget style

Adding the possibility to style also the anchor elements inside a list

Close #787
fix #748 debug tools: "reload with source" button no longer appears

This commit fixes a regression introduced in Aria Templates 1.4.10
by commit 222411636510b08270641db78fd9a8463d078f8b: when typing in
the text area in the debug tools to change the template, the
"Reload with source" button no longer appears.

Close #764
feat #784 Updating overlay property

Adding border-radius to the overlay property

Close #784
feat #783 Adding font-size and mouse over property to the skin

Making the calendar font-size, border, background-color and color on mouse over customizables

Close #783