Add support of wildcards

[Koc]

For example have 2 actions: addProductToCart, refreshCart. Each of they call startLoading(dispatcher, 'cart') on method enter and endLoading(dispatcher, 'cart') before each return. The problem occurs when addProductToCart calls refreshCart inside. End loading occurs too early.

It is similar to nested transactions.

[f]

Do not use same loading key for different actions. You should use startLoading(d, 'adding product to card') and startLoading(d, 'refreshing cart'). And you can watch $loader.isLoading(['adding product to cart', 'refreshing cart']) to wait both of loaders to be finished.

[Koc]

This can be sollution but not for all cases. For example we loading products

startLoading(dispatcher, `products.${id}`)

and I should make check for any loading products: $loader.isLoading('products.*') but asterisk syntax not supported.

[f]

@Koc this looks nice.

[f]

Please review v1.0.0 PR. It now supports RegExp check for isLoading.

isLoading(/products\..*/) will work.

[Koc]

covered by #31