Total number of items in collection should not be ambiguous

[zrthxn]

Both ChRIS API and Store API, transform the total count of items in any collection to an ambiguous value. If the total item count is greater than zero, it returns totalCount: total; But if it is zero, it returns totalCount: -1 which is counter-intuitive and ambiguous.
If this value is meant to represent errors, those should be represented by the function throwing an error rather than returning a value.

[jennydaman]

fnndsc/js/chrisAPI/src/cj.js

Lines 62 to 75 in 9b8b604

	/**
	* Get the total number of items from a collection object.
	*
	* @param {Object} collection - Collection+Json collection object
	*
	* @return {number} - total number of items or -1 if the collection objects
	* doesn't contain that information
	*/
	static getTotalNumberOfItems(collection) {
	if (collection.total) {
	return collection.total;
	}
	return -1;
	}