Corrects `navSpeed` option in navigation plugin

See #137
Merge pull request #141 from witrin/navigation

Corrects `navSpeed` option in navigation plugin
Touch and Mouse handlers tests

This is branch for mouse/touch tests on tablet-pc (windows 8 pc with
touch screen)
Minor fixes
Merge branch 'touchhandlers' into develop
Fixed Hash object destruction
Corrects interface of `add` in core

See #125