update elements and fix some bugs

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

 Prism.languages.matlab = {
         // We put string before comment, because of printf() patterns that contain "%"
-        'string': {
-                pattern: /(^|\W)'(?:''|[^'\n])*'/,
-                lookbehind: true
-        },
+        'string': /\B'(?:''|[^'\n])*'/,
         'comment': [
                 /%\{[\s\S]*?\}%/,
                 /%.+/
         ],
         // FIXME We could handle imaginary numbers as a whole
         'number': /\b-?(?:\d*\.?\d+(?:[eE][+-]?\d+)?(?:[ij])?|[ij])\b/,
         'keyword': /\b(?:break|case|catch|continue|else|elseif|end|for|function|if|inf|NaN|otherwise|parfor|pause|pi|return|switch|try|while)\b/,
         'function': /(?!\d)\w+(?=\s*\()/,
         'operator': /\.?[*^\/\\']|[+\-:@]|[<>=~]=?|&&?|\|\|?/,
         'punctuation': /\.{3}|[.,;\[\](){}!]/
 };