Datasource settings: Make HTTP all caps

It's an acronym, so it should be all caps.

public/app/features/plugins/partials/ds_http_settings.html

@@ -1,7 +1,7 @@
 
 
 <div class="gf-form-group">
-  <h3 class="page-heading">Http settings</h3>
+  <h3 class="page-heading">HTTP settings</h3>
   <div class="gf-form-group">
     <div class="gf-form-inline">
       <div class="gf-form max-width-30">
@@ -38,7 +38,7 @@
     </div>
   </div>
 
-  <h3 class="page-heading">Http Auth</h3>
+  <h3 class="page-heading">HTTP Auth</h3>
     <div class="gf-form-group">
       <div class="gf-form-inline">
         <gf-form-switch class="gf-form" label="Basic Auth" checked="current.basicAuth" label-class="width-8" switch-class="max-width-6"></gf-form-switch>