Demo tweaks

Nav: Tweaked default highlight clipping (clipped by scrollbar) and removed subtle background (#323)

Nav: Added ImGuiCol_NavWindowingHighlight into style (#323)

Nav: Fixed bug where pressing NavInput(Triangle) to turn slider/drag into text input would then change subsequent NavActivate as well (#323)

Nav: Allow PadLeft to close a menu (#323)

Merge remote-tracking branch 'origin' into 2016-07-navigation

BulletText(): doesn't stop displaying at the ## mark

Nav: Failed movement request with no current NavId fallback to an InitDefaultRequest so that we always land somewhere on first move (#323)

Nav: Comments (#323)

Merge remote-tracking branch 'origin' into 2016-07-navigation

Removed a handful of obsolete (trivial) function redirection from 1.34 and 1.38 (march-april 2015) ...

OpenNextNode() -> SetNextTreeNodeOpen()
GetWindowIsFocused() -> IsWindowFocused()
GetItemBoxMin() -> GetItemRectMin()
GetItemBoxMax() -> GetItemRectMax()
IsMouseHoveringBox() -> IsMouseHoveringRect()
IsClipped() -> !IsRectVisible()

Merge branch 'thedmd-2016-08-generalized_visibility_test'

Tweak comments (#768)

Merge branch '2016-08-generalized_visibility_test' of https://github.com/thedmd/imgui into thedmd-2016-08-generalized_visibility_test

Using IM_COL32() for colors in a few spots (#767)

Moved GetColorU32 out of imgui_internal.h to avoid inlining mess (#759)

Add ability to test arbitrary rectangle for visibility without need of moving cursor.

Nav: Reordered Cancel handling code so you you can leave a child within a popup without closing the popup (#323)

Nav: Menu: Allow PadDown to open a menu from a menu bar, PadRight from a menu (#323, #126)

Nav: Moving all nav inputs to io.NavInputs[] float array, new enum labelled for gamepad. (#323)

Typo in commented default-value

Nav: Moving window with nav stick disables mouse hover (#323)

Demo: Arrange some inputs panels.

Nav: DragBehavior removed bogus test (#323)

Demo: Tweak handling of "animate" flag in graph demo so it doesn't keep running.

Merge remote-tracking branch 'origin' into 2016-07-navigation

Using ImGuiID instead of ImU32 is a few places

Nav: quick tap on NavMenu with no focused window doesn't focus one (holding still does) (#323)

Nav: fixed using NavMenu/windowing select when no window is already focused + cleanup code (#323)

Nav: working on early bits of documentation (#323)