new:
- added open_delay attribute (in ticks) for backpacks. You can now create backpacks that require some seconds to open. https://github.com/PluginBugs/Issues-EpicBackpacks/issues/33
- added UltimateStacker compatibility. https://github.com/PluginBugs/Issues-EpicBackpacks/issues/35
- added options in config.yml to allow empty backpacks to be put in enderchests and shulkers https://github.com/PluginBugs/Issues-EpicBackpacks/issues/25

fixes:
- fixed Backpacks put in Enderchest https://github.com/PluginBugs/Issues-EpicBackpacks/issues/32
- fixed duplication bug with EpicBackPack 1.8.9 https://github.com/PluginBugs/Issues-EpicBackpacks/issues/34
- fixed duplication exploit with hacked clients