chore(dependencies): update istanbul to 0.3.0

use new features like reporters e.g. json-summary
use  svg badge by default
Merge pull request #93 from sahat/patch-1

use  svg badge by default
Merge pull request #88 from robinboehm/master

chore(dependencies): update istanbul to 0.3.0
chore: release v0.2.6
docs(readme): add an advanced usage example
Merge branch 'master' into fix-skip-dir-creation
test: split up directory creation test