Missing declaration tutorial

[dylans]

The tutorial from https://github.com/dojo/dojo-website/tree/master/src/documentation/tutorials/1.9/declaration was never ported for 1.10. This breaks the link to https://dojotoolkit.org/documentation/tutorials/1.10/declaration/ from the bottom of https://dojotoolkit.org/documentation/tutorials/1.10/declarative/

Note that for now the tutorial may be viewed at https://dojotoolkit.org/documentation/tutorials/1.9/declaration/ .