Fix float right overflow (#8557)

* tc-subtitle is not a sibling to tc-body,
So tc-subtitle needs a clearfix to contains float:right

* add clearfix to all tiddler elements that could contain floats

* add clearfix to tc-tiddler-title in ViewTemplate

* add clearfix to plugin/blog/templates

* add clearfix to plugin/tour/templates

* remove test tiddler

* rename draft title class to tc-tiddler-title-draft

* undo title field covering

* move tc-clearfix to tc-float-right in the base CSS file

* rename clearfix CSS class to tc-clearfix

* update documentation tiddlers

core/templates/server/static.tiddler.wikitext.tid

@@ -1,23 +1,23 @@
 title: $:/core/templates/server/static.tiddler.wikitext
 
 \whitespace trim
-<div class="tc-tiddler-title">
+<div class="tc-tiddler-title tc-clearfix">
 <div class="tc-titlebar">
 <h2><$text text=<<currentTiddler>>/></h2>
 </div>
 </div>
-<div class="tc-subtitle">
+<div class="tc-subtitle tc-clearfix">
 <$link to={{!!modifier}}>
 <$view field="modifier"/>
 </$link> <$view field="modified" format="date" template={{$:/language/Tiddler/DateFormat}}/>
 </div>
-<div class="tc-tags-wrapper">
+<div class="tc-tags-wrapper" tc-clearfix>
 <$list filter="[all[current]tags[]sort[title]]">
 <a href={{{ [<currentTiddler>encodeuricomponent[]] }}}>
 <$macrocall $name="tag-pill" tag=<<currentTiddler>>/>
 </a>
 </$list>
 </div>
-<div class="tc-tiddler-body">
+<div class="tc-tiddler-body tc-clearfix">
 <$transclude mode="block"/>
 </div>