dialog.validate.functions bugs

[Michael Johnson]

The definition of the function returned from dialog.validate.functions suffers from two bugs.

1) When obtaining the "value" from the arguments, the inner function should be referencing its own arguments, not those of the outer function. 2) When calling functions, it should be using "call" and passing "this" so that other validation functions passed as arguments will have the item as "this" as they expect.

[Michael Johnson]

Patch to plugins.dialog.plugin.js