Rename Ext.net.HyperlinkButton component's toggle() function to toggleEnabled()

[fabriciomurta]

The function in Ext.NET context will toggle the enabled state of the button. It now conflicts with Ext.button.Button which calls it on click!..

To avoid a breaking change, #1448 makes it take different behavior according to the caller:

• whenever it is Ext.button.Button.doToggle(), call parent toggle() (if any)
• whenever else, does its usual enabled state toggle.

[fabriciomurta]

Function renamed to toggleEnabled() instead.

So, to implement the fix, server-side method ToggleEnabled() was introduced, and client-side toggleEnabled() function was renamed, from toggle() that was present in the Ext.net.HyperlinkButton definition.

As the Hyperlink button inherits from the simple button, then it gets the toggle() client and server side methods.