gulp rev all not including non css/js files

[ccorda]

Don't believe this was always the case, but noticed only css and js files are appearing in the manifest: https://github.com/smysnk/gulp-rev-all/issues/224

Was trying to rev some fonts, and they weren't working.

Two things:

1) We should fix with this code:

let extensions = [
    '.html',
    '.css',
    '.js',
    '.png',
    '.jpg',
    '.jpeg',
    '.gif',
    '.svg',
    '.woff',
    '.woff2',
    '.ttf',
    '.eot',
    '.otf',
  ];

  $.revAll.revision({ dontSearchFile: ['.js'], includeFilesInManifest: extensions }),

2) If a file isn't found in the manfiest, we should still output the original path.