Rejig the tabs macro to wikify captions

This will allow us to translate tab captions

core/ui/PageMacros.tid

@@ -1,7 +1,7 @@
 title: $:/core/ui/PageMacros
 
 \define tabs(tabsList,default,state:"$:/state/tab")
-<div class="tw-tab-buttons"><$list filter="$tabsList$" variable="currentTab"><$button set=<<qualify "$state$">> setTo=<<currentTab>> default="$default$" selectedClass="tw-tab-selected"><$view tiddler=<<currentTab>> field="caption"><$macrocall $name="currentTab" $type="text/plain" $output="text/plain"/></$view> </$button>
+<div class="tw-tab-buttons"><$list filter="$tabsList$" variable="currentTab"><$button set=<<qualify "$state$">> setTo=<<currentTab>> default="$default$" selectedClass="tw-tab-selected"><$transclude tiddler=<<currentTab>> field="caption"><$macrocall $name="currentTab" $type="text/plain" $output="text/plain"/></$transclude> </$button>
 </$list>
 </div>
 <div class="tw-tab-divider">