Milestone Levels

Display level and XP milestones on a fancy league-like notification

level, skill, xp, experience, notification, notifier, milestone, attack, defence, strength, hitpoints, ranged, prayer, magic, cooking, woodcutting, fletching, fishing, firemaking, crafting, smithing, mining, herblore, agility, thieving, slayer, farming, runecraft, hunter, construction, sailing