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()

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)

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

Nav: DragBehavior removed bogus test (#323)

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)

Nav: Not exposing ImGuiWindowFlags_NavFlattened because it requires much more work (#323)

Nav: Merge FocusedWindow and NavWindow that were basically duplicate at this point (#323)

Tidying up, removed two unnecessary window flags from being exposed in imgui.h

Nav: Added experiment ImGuiWindowFlags_NavFlattened flag to cross over between parent and non-scrolling child windows (#323)

Nav: No scrolling while using windowing functionalities (#323)

Nav: MoveRequest doesn't affect io.NavUsable so that navigation failure doesn't trigger false positive & not needed (undo part of 3cc1419df)

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

SameLine() with explicit X position is relative to left of group/columns (ref #746, #125, #630)