Hard coded start & end symbols can cause rendering issues

[toddrun]

I use different start and end symbols in my angular app:

config(function($interpolateProvider){
    $interpolateProvider.startSymbol('{[{').endSymbol('}]}');
})

Unfortunately, that isn't honored by angular-prompt. It would be helpful to have the start and end symbols dynamically set.

[AndreasLoukakis]

@toddrun a frew days before you submited the issue, I made a pull request fixing this exact same thing. Just letting you know here in case you would like to take a look as @cgross hasn't checked it out obviously.

[toddrun]

@AndreasLoukakis, that's awesome! The project where I'm using angular-prompt is currently in code freeze, but hopefully your fix will get in soon.