RAA - depq/0.4

depq is double-ended stable priority queue with priority update operation implemented using implicit heap.

• queue - you can insert and delete values
• priority - you can get a value with minimum priority
• double-ended - you can get a value with maximum priority too
• stable - you will get the value inserted first with minimum/maximum priority
• priority update - usable for Dijkstra's shortest path algorithm and various graph algorithms
• implicit heap - compact heap representation using array. most operations are O(log n) at worst
• iterator operations: nlargest, nsmallest and merge