Plan and done for June-17-2017

What is this all about - http://al1s.github.io/posts/plan-and-done-for-may-25-2017/.

Day 18 - sum up time periods in data-* attributes of list items on a page using reduce.

Implemented a function for calculating total time summing arguments passed as a string each. The challenge was in passing list of arguments that I've got from a nodeList object - it continuisly passed to the function as a string, but not a list of arguments or an array. Finally I've filled an array explicitly.

Here is working example - https://al1s.github.io/JavaScript30//index.html.