[Seaside] ShoreComponents for Seaside 2.6

[Pavel Krivanek]

Hi all

I'm upgrading ShoreComponents for Seaside 2.6a. SqueakSource seems to be 
down so you can find the first version here: 
ftp://comtalk.net/pub/shore/ShoreComponents-2.6-pk.1.mcz. It's not 
completed but the most important components like rich edit and date 
picker are already upgraded.

The version for Seaside 2.6 will *not* be backward compatible. It uses 
new Canvas API and Sctiptaculous.

It introduces new way how to solve problem of nested forms. 
ShoreComponts may use two brushes for forms - ShoreFormTag and 
ShoreNestedFormTag. While a component is creating simple form, it stores 
this brush to its attributes. This attribute is cleared before every 
next rendering of the component. All nested forms are then simulated by 
divs. ShoreNestedFormTag points to parent form brush and delegates 
changes of attributes to it.

Seaside renders opening form tag immediately and all next changes to 
form attributes cannot be written. Therefore ShoreFormTag creates new 
temporary stream for form content that replaces current stream of the 
document. Opening form tag so can be rendered after processing of all 
children that may modify form attributes.

As result of it we may now use standard canvas API syntax for all forms.

-- Pavel