Closure issue for .disable() and .enable() functions

[jchristman]

For the .disable() and .enable() functions, the function always applies to which is the last button in the array. That is, calling .disable() on a button may not always disable that button. See this for details on closure problems.

I am submitting a pull request that fixes this problem, while also making two more fields reactive: "closeModalOnClick" and "label".