Don't use "line-through" style for completed items in remarkup checklists

Summary: Fixes T13482. Although this style makes physical sense by relationship to a written checklist, it seems to do more harm than good in practice.

Test Plan: Wrote a checklist with a checked-off item in remarkup, saw no more line-through.

Maniphest Tasks: T13482

Differential Revision: https://secure.phabricator.com/D20954

resources/celerity/map.php

@@ -9,7 +9,7 @@ return array(
   'names' => array(
     'conpherence.pkg.css' => '3c8a0668',
     'conpherence.pkg.js' => '020aebcf',
-    'core.pkg.css' => 'fd35999c',
+    'core.pkg.css' => 'ad8fc332',
     'core.pkg.js' => '705aec2c',
     'differential.pkg.css' => '607c84be',
     'differential.pkg.js' => '1b97518d',
@@ -112,7 +112,7 @@ return array(
     'rsrc/css/application/tokens/tokens.css' => 'ce5a50bd',
     'rsrc/css/application/uiexample/example.css' => 'b4795059',
     'rsrc/css/core/core.css' => '1b29ed61',
-    'rsrc/css/core/remarkup.css' => 'f06cc20e',
+    'rsrc/css/core/remarkup.css' => 'c286eaef',
     'rsrc/css/core/syntax.css' => '220b85f9',
     'rsrc/css/core/z-index.css' => '99c0f5eb',
     'rsrc/css/diviner/diviner-shared.css' => '4bd263b0',
@@ -794,7 +794,7 @@ return array(
     'phabricator-object-selector-css' => 'ee77366f',
     'phabricator-phtize' => '2f1db1ed',
     'phabricator-prefab' => '5793d835',
-    'phabricator-remarkup-css' => 'f06cc20e',
+    'phabricator-remarkup-css' => 'c286eaef',
     'phabricator-search-results-css' => '9ea70ace',
     'phabricator-shaped-request' => 'abf88db8',
     'phabricator-slowvote-css' => '1694baed',

webroot/rsrc/css/core/remarkup.css

@@ -155,7 +155,6 @@
 
 .phabricator-remarkup .remarkup-list-with-checkmarks .remarkup-checked-item {
   color: {$lightgreytext};
-  text-decoration: line-through;
 }
 
 .phabricator-remarkup ul.remarkup-list ol.remarkup-list,