Article or other text pagination helper

[eluser]Jelmer[/eluser]
Wow, I forgot about this helper (even though it's integrated into a CMS of mine). There's a lot of inefficiency in it: the use of ereg instead of preg for regular expressions and ereg where also strpos(), str_replace() or even substr() could be used. Also the use of count() within the definition of a for-loop (which caused the function call on each iteration).
I'll rewrite this shortly to make it a lot more efficient.

Also: arguements 2,3 and 4 aren't necessary - they can all be gotten from the CI superobject with get_instance().

@theprodigy: this doesn't have anything to do with my helper, it should have it's own topic.