Update 16

Rename deepDestruction to destroyChildren.

Add Utilities.URL.strip to simplify the removal of ? and # from a URL.

Use direct compares for undefined instead of typeof.

Use string concatenation instead of array joining.

Properly implement kept and unkept snapshots.

Snapshots can now be named.

Checking for expired Store items now occurs at an interval of 25% of the maxLife.

Move Store#toJSON to Store#readyJSON. Created Store#toJSON to call Store#readyJSON without any arguments. This avoids the weird swapPrefix issue where "value" was being set.