InfoClick prop filters - Allow props as filter arguments

[jesade-vbg]

There are actually 2 related things that should/could be adressed at the same time.

1. The first thing is that comma (,) cant be used in an argument because split(',') is used.
   Example of what breaks the rendering: {propName|fallback('This string will be cut, yes it will.')}

2. The second thing that would be nice is to be able to use a prop as an argument.
   Example: {propName1|fallback(propName2)|toUpper}
   Triple fallback example (In theory) :) : {propName1|fallback(propName2)|fallback(propName3)|fallback('Hey! You got no value!')}

[jacobwod]

BTW @jesade-vbg, we should really remember to document this kind of stuff in the Wiki (unless it's already done of course!). Nice addition, but it won't get a lot of CPU cycles unless admins know about this. 😉

[jesade-vbg]

Haha yes! My dog ate the documentation I wrote so I guess I'll have to write it again. Thanx for the reminder :)

[jesade-vbg]

Docs added to wiki. (props as filter args, subscript, superscript)