Parser: allow multiple comments

Since it’s only used for reference locale, read metadata in a second
pass on the file content, consider comments as an array.
CSS: cleanup, load font from https

Clean CSS bedrock-style, fix the Open Sans problem.
Merge pull request #149 from flodolo/fix_css

CSS: cleanup, load font from https
Merge pull request #148 from flodolo/metadata_extraction

Parser: allow multiple comments