Rework LibGroupTalents now also returns function returns additionally, add Spec Role triggers to load/generic/bt2, fix WeakAuras.GetRegion

- **WeakAuras.SpecForUnit(unit)** = Returns: `classFileName..spec`, `Dominant Tree`, `spent1`, `spent2`, `spent3`
- **WeakAuras.GetUnitRole(unit)** = Returns one of: `"melee"`, `"caster"`, `"healer"`, `"tank"`
- **WeakAuras.SpecRolePositionForUnit(unit)** = Returns: `Dominant Tree`, `spent1`, `spent2`, `spent3`
- **WeakAuras.CheckTalentForUnit(unit, talentId)** = Returns: `"Points spent"` in talent or `nil`
- **WeakAuras.CheckGlyphForUnit(unit, glyphId)** = Returns: `true` if the player has the glyph associated with `spellID` or `spellName`, we can only see the glyphs of players running `LibGroupTalents-1.0`

WeakAuras/GenericTrigger.lua

@@ -3025,6 +3025,12 @@ function WeakAuras.WatchUnitChange(unit)
         eventsToSend["UNIT_ROLE_CHANGED_" .. unit] = unit
         watchUnitChange.unitRaidRole[unit] = newRaidRole
       end
+      local oldRole = watchUnitChange.unitRoles[unit]
+      local newRole = WeakAuras.GetUnitRole(unit)
+      if oldRole ~= newRole then
+        eventsToSend["UNIT_ROLE_CHANGED_" .. unit] = unit
+        watchUnitChange.unitRoles[unit] = newRole
+      end
     end
 
     local function handleUnit(unit, eventsToSend, ...)