update elements and fix some bugs

lib/src/prism/components/prism-crystal.js

+(function(Prism) {
+        Prism.languages.crystal = Prism.languages.extend('ruby', {
+                keyword: [
+                        /\b(?:abstract|alias|as|asm|begin|break|case|class|def|do|else|elsif|end|ensure|enum|extend|for|fun|if|ifdef|include|instance_sizeof|lib|macro|module|next|of|out|pointerof|private|protected|rescue|return|require|self|sizeof|struct|super|then|type|typeof|union|unless|until|when|while|with|yield|__DIR__|__FILE__|__LINE__)\b/,
+                        {
+                                pattern: /(\.\s*)(?:is_a|responds_to)\?/,
+                                lookbehind: true
+                        }
+                ],
+
+                number: /\b(?:0b[01_]*[01]|0o[0-7_]*[0-7]|0x[0-9a-fA-F_]*[0-9a-fA-F]|(?:[0-9](?:[0-9_]*[0-9])?)(?:\.[0-9_]*[0-9])?(?:[eE][+-]?[0-9_]*[0-9])?)(?:_(?:[uif](?:8|16|32|64))?)?\b/,
+        });
+
+        var rest = Prism.util.clone(Prism.languages.crystal);
+
+        Prism.languages.insertBefore('crystal', 'string', {
+                attribute: {
+                        pattern: /@\[.+?\]/,
+                        alias: 'attr-name',
+                        inside: {
+                                delimiter: {
+                                        pattern: /^@\[|\]$/,
+                                        alias: 'tag'
+                                },
+                                rest: rest
+                        }
+                },
+
+                expansion: [
+                {
+                        pattern: /\{\{.+?\}\}/,
+                        inside: {
+                                delimiter: {
+                                        pattern: /^\{\{|\}\}$/,
+                                        alias: 'tag'
+                                },
+                                rest: rest
+                        }
+                },
+                {
+                        pattern: /\{%.+?%\}/,
+                        inside: {
+                                delimiter: {
+                                        pattern: /^\{%|%\}$/,
+                                        alias: 'tag'
+                                },
+                                rest: rest
+                        }
+                }
+                ]
+        });
+
+}(Prism));