Use everyItem or itemByRange instead of loops for better performance in core

[ff6347]

As mentioned in issue #44

[ff6347]

I've been snooping around the source. Actually there are not a lot of for loops used to get elements. 👍 There are some forEach loops though. these can't be replaced by a everyitem() call. The everyItem or itemByRange can be used to set properties but there is no way to run a function on each item.

[b-g]

Many thanks for double checking this nitty gritty performance detail!! I guess we can close the issue then?

[ff6347]

Yes we can.