Separate Sticky and Normal Threads (XF +2.x) by Xon 2.2.0

This addon is now available on https://atelieraphelion.com

• Require StandardLib v1.21.0+
• XF2.3 compatibility update for "Collapsible stickies threads block" feature

• Require StandardLib v1.19.0+
• Require XenForo 2.2+
• Move template code into a macro instead of the template modification
• Add "Collapsible stickies threads block" style property (default disabled)
  • This feature is not yet XF2.3 compatible

• Fix unexpected height of stick/normal thread banner for mobiles

• Ensure structured list css/less is loaded when no threads are selected

This add-on appears to have no compatibility issues with XF2.1

• Tweak execution order of class extensions/template modifications/etc to provide predictable ordering
• Add LICENCE and README.MD to redistributable.