We are all familiar with the concept of layering, especially here in Nova Scotia where the weather can go from snow, to rain to humid and hot -not only in a matter of hours but within the distance of a few kilometers. (Everyone knows Mount Uniacke has its own weather system, am I right?) But what if you are heading out on a day hike on a sticky July Saturday? Here ,in a nutshell, is what you need to know when thinking about hiking clothing for summer.        Bottom line for  hiking tops: Cotton breathes  & soaks up sweat-which can keep you cool but also allow you to…