Version 2.2 compatibility

[dexbarrett]

I used this package before with Laravel 4 and it worked like a charm. Now I was using the version 2.2 with a Laravel 5.1 app and it seems like the different ways of registering shortcodes don't really work with this version of the library.
I was looking at the code and noticed it now uses a package named thunderer/shortcode which validates that the function that will parse the shortcode is a callable, which will throw an error when trying to use for example the syntax 'ClassPath@method' or just 'ClassPath' (assuming the class has a register method defined). So the current version only supports a closure or anything that can be called as a function. I can confirm this because I updated my composer.json file to use the version 2.1 instead and now it works.

[simonfunk]

Same issue here. since the last composer update with "~2.1" it throws the error, now i've temporarly fixed by version 2.1