document route props passing to route handlers

closes #155
add ticks to docs
[fixed] Navigation to root URL can fail

Navigation to root URL can fail when the URLStore is setup with
location strategy 'hash'. This happens because URLStore.push
verifies the current path. Unfortunately the used currentPath is
not valid for the location strategies *hash* and *history*.

This change changes URLStore.push so that it uses the location
strategy specific current path. This value is already provided
by URLStore.getCurrentPath.
Merge pull request #163 from bripkens/failing-navigation

[fixed] Navigation to root URL can fail
[fixed] location="history" fallback
fixed getCurrentPath with disabledHistory
release v0.5.1
[added] onActiveStateChange, onCancelledTransition, onTransitionError Routes props

Also, removed Routes.handleAsyncError and Routes.handleCancelledTransition