fixed win8 support
updated docs
updated docs
Update README.md
added prevent_default option with documentation about it, fixes #152
prevent default option, instance returns itself to make it chainable
changes
Added drag_lock_to_axis option, which keeps the drag gesture on the axis that it started on, ie. disallows vertical directions if the initial direction was horizontal, and vice versa.

Also corrected some comment typos.
Added drag_lock_to_axis option, which keeps the drag gesture on the axis that it started on, ie. disallows vertical directions if the initial direction was horizontal, and vice versa.