Fix BottomTabs / MaterialTopTabs tabBar props (#33)

* update tabBarComponent to tabBar in MaterialTopTab

* update tabBarComponent to tabBar in BottomTab

Author: Freddy03h

src/BottomTabs.re

@@ -176,7 +176,7 @@ module Make = (M: {type params;}) => {
         ~screenOptions: optionsCallback=?,
         ~children: React.element,
         ~_lazy: bool=?,
-        ~tabBarComponent: React.component(Js.t(bottomTabBarProps))=?,
+        ~tabBar: React.component(Js.t(bottomTabBarProps))=?,
         ~tabBarOptions: bottomTabBarOptions=?,
         unit
       ) =>

src/MaterialTopTabs.re

@@ -189,7 +189,7 @@ module Make = (M: {type params;}) => {
                                      "route": route(M.params),
                                    })
                                      =?,
-        ~tabBarComponent: React.component(Js.t(materialTopTabBarProps))=?,
+        ~tabBar: React.component(Js.t(materialTopTabBarProps))=?,
         ~tabBarOptions: materialTopTabBarOptions=?,
         ~tabBarPosition: [@bs.string] [ | `top | `bottom]=?,
         unit