update to higlight.js 8.4

vendor/assets/javascripts/highlight_js/languages/step21.js

@@ -0,0 +1,61 @@
+/*
+Language: STEP Part 21 (ISO 10303-21)
+Contributors: Adam Joseph Cook <adam.joseph.cook@gmail.com>
+Description: Syntax highlighter for STEP Part 21 files (ISO 10303-21).
+*/
+
+function(hljs) {
+  var STEP21_IDENT_RE = '[A-Z_][A-Z0-9_.]*';
+  var STEP21_CLOSE_RE = 'END-ISO-10303-21;';
+  var STEP21_KEYWORDS = {
+    literal: '',
+    built_in: '',
+    keyword:
+    'HEADER ENDSEC DATA'
+  };
+  var STEP21_START = {
+    className: 'preprocessor',
+    begin: 'ISO-10303-21;',
+    relevance: 10
+  };
+  var STEP21_CODE = [
+    hljs.C_LINE_COMMENT_MODE,
+    {
+      className: 'comment',
+      begin: '/\\*\\*!', end: '\\*/',
+      contains: [hljs.PHRASAL_WORDS_MODE]
+    },
+    hljs.C_BLOCK_COMMENT_MODE,
+    hljs.C_NUMBER_MODE,
+    hljs.inherit(hljs.APOS_STRING_MODE, {illegal: null}),
+    hljs.inherit(hljs.QUOTE_STRING_MODE, {illegal: null}),
+    {
+      className: 'string',
+      begin: "'", end: "'"
+    },
+    {
+      className: 'label',
+      variants: [
+        {
+          begin: '#', end: '\\d+',
+          illegal: '\\W'
+        }
+      ]
+    }
+  ];
+
+  return {
+    aliases: ['p21', 'step', 'stp'],
+    case_insensitive: true, // STEP 21 is case insensitive in theory, in practice all non-comments are capitalized.
+    lexemes: STEP21_IDENT_RE,
+    keywords: STEP21_KEYWORDS,
+    contains: [
+      {
+        className: 'preprocessor',
+        begin: STEP21_CLOSE_RE,
+        relevance: 10
+      },
+      STEP21_START
+    ].concat(STEP21_CODE)
+  };
+}