fixed sticky slidemenu

1. Issue: 

two issues with slide menu: 
- when swiping to reveal side menu, it some times gets stuck in between, does not close completely or open completely. 
- another issue is that swipe only works when it is started within the left 256px of the panel (width of side menu)


2. Test case:

open the af kitchensink app, and swipe right to open sidemenu and swipe down at the same time, notice that it gets stuck in between.

also u cannot start swipe from the rightside of the panel, swipe can only be started within the left 256px of panel.


3. Fix description:

- this fixes the sticky issue:
removed "doMenu = false" in "if (Math.abs(dy - startY) > Math.abs(dx - startX))" -> this was leaving the panel stuck in between, without this it will snap to either open or close. 


- this fixes the slide start position, so now u can slide anywhere on panel to reveal the side menu:
removed "if (dx > max) return true;" -> this was only allowing panel swipe starting within the first 256px (width of sidemenu).
if (dx-startX > max) return true; -> will make sure that panel will not slide out more that the width of side menu
if (startX-dx > max) return true; -> will make sure that panel will not slide in more that the width of side menu