feat(rxPermission): add ability to match against multiple roles

Allow to pass a list of comma delimited role names to the directive in order to match against any of them.
The convention I've been using is, if a variable is being set, it should have its own `var`. So:
```
var permissionSvc = {};
var trim = ...;
var call = ...;
```

Only if we're not setting an initial value do we combine the vars.
```
var x, y, z;
```