hg: don't use custom diff arguments when generating diffstats for rss feed With Mercurial 4.7, it is no longer possible to pass arguments like `git=True` to `ctx.diff()`. This will change the reported data slightly, but the difference isn't important. Also, the code should be refactored to do something similar to what we do in other places.

{
  "name": "kallithea",
  "private": true,
  "dependencies": {
    "bootstrap": "3.3.7"
  },
  "devDependencies": {
    "less": "~2.7",
    "less-plugin-clean-css": "~1.5"
  },
  "scripts": {
    "less": "lessc --relative-urls --source-map --source-map-less-inline kallithea/public/less/main.less kallithea/public/css/style.css"
  }
}