Parametrize application root
Define base app root
Router should use relative paths only
Navigate to paths with appRoot
Docs on using appRoot
appRoot must be empty by default
Test that appRoot is defined
Navigate to relative paths
Merge pull request #69 from varya/features/not-root-dir

The UI should work even if it does not run on HTTP root dir
Improve README and package.json description
Merge pull request #70 from hannu/improve-readme-options

Improve README and package.json description