Merge pull request #8 from ionum/master

German translation
updated German translation
better detection of RSS feeds and news
small change in displaying of DKIM-Signature header
fixed relaxed canonicalization from a body with only empty lines (by ionum, fixes #9)
header highlighting now works with collapsed header from CompactHeader addon
Merge branch 'master' of https://github.com/lieser/dkim_verifier