All versions of Grips & Grades hangboard app

- Three new hangboards added: Tension Grindstone Mk2, Strong Ant III and Linebreaker Base target 10a - Added Custom grade, where workouts are generated based on various filter settings. Those filter settings are behind filter icon (Custom grade menu item) -> There user can change minimum and maximum hold difficulty, include and exclude wanted grip types and sort hold list for example based on difficulty.