add vertical_align to UnderlineContainer
Merge branch 'new_ui_code' of github.com:hwhw/kindlepdfviewer into new_ui_houqp
add width and invert to FrameContainer
add iconbutton widget
return true on iconbutton click event
first demo of touch menu
fix: set parent on TouchMenuItem
use touchmenu widget in readermenu
minor fixes, add TouchMenu example to wtest.lua
add resources for ReaderMenu
put menu item callback and closing ops to scheduler

Otherwise, inverted menu item will not be shown
add submenu support for touchmenu
add LvDEBUG

so we can get rid of stack overflow when dumping a widget
add go back button to touchmenu
give a better name for parent
update wtest according to new touchmenu api
Merge pull request #798 from houqp/new_ui_houqp

add touchmenu
bugfix: clamp scroll offsets
Merge pull request #799 from chrox/new_ui_code

bugfix: clamp scroll offsets
comments for clamping scroll offsets