Improve error reporting
Update README
Merge pull request #11 from macbre/error-reporting

Improve error reporting
Add Bitdeli badge
Add universal selector metric
Merge pull request #14 from macbre/universal-selectors

Add universal selector metric
Rules with comments should be treated as an empty ones
Merge pull request #16 from macbre/empty-rules-with-a-comment

Rules with comments should be treated as an empty ones
Report outdated CSS prefixes - data generator
oldPropertyPrefixes: add a metric
Add unit tests
Merge pull request #19 from macbre/outdated-vendor-prefixes

Report outdated CSS prefixes
Update README
README: Dev hints
Update README.md
Report total length of base64-encoded data
Update README
Merge pull request #20 from macbre/base64-length

Report total length of base64-encoded data
Prefixes: improvements

* better messages on why prefix needs to be kept / can be removed
* pretty-pring JSON with prefixes
* debugging
Debugging: update README