#7 config.xml improvements

[Thomas Fischer]

This patch adds several features/changes to middleman's standard
config.xml:
- User agent: Using Konqueror 3.2 instead of M$ IE
- Use cesnet instead of telia for Sourceforge downloads (Telia
seems to not mirroring everything)
- Three new ad blocker rules (e.g. from Google)
- Replacement of non-standard fonts like Arial or Verdana by
"sans-serif". Three rewrite rules for HTML and CSS

[Thomas Fischer]

Patch vor middleman/config.xml