Fix urls resolving.

It was broken and was ignoring rootUrl value to map urls
into path on local file system.

Refs #78
Fix stats processing

When some file was included in several tests coverage was calculated
separately for every case and report file was overwritten by the latest
iteration.

Closes #72
Add sorting feature to the coverage index;
Colorize index items depending on the coverage level
Merge pull request #79 from bem/feature/sort

Add sorting feature to the coverage index. Colorize index items depending on the coverage level
0.9.0