impl theme selector

adjust styles

resource/css/_form.scss

@@ -208,6 +208,12 @@
     border-top: solid 1px #ccc;
     margin-bottom: 0;
   }
+
+  #page-editor-theme-selector .theme-selector {
+    label {
+      margin-right: 0.5em;
+    }
+  }
 } // }}}
 
 .crowi.main-container .main .page-list.content-main { // {{{ Edit Form of Page List

resource/js/components/PageEditor/ThemeSelector.js

@@ -35,7 +35,7 @@ export default class ThemeSelector extends React.Component {
     });
 
     return (
-      <FormGroup controlId="formControlsSelect">
+      <FormGroup controlId="formControlsSelect" bsClass="theme-selector">
         <ControlLabel>Theme:</ControlLabel>
         <FormControl componentClass="select" placeholder="select"
             onChange={this.onChange}