Internal tidying up, moved code to CalcNextScrollFromScrollTargetAndClamp() so it can be reused by upcoming nav code.

ImRect: Added Translate() helper, removed redundant and misleading Reduce()

Added IsItemHoveredOrFocused() (provisional name), better handling of popup/tooltip positioning when using mouse+nav (#323)

Nav: Fixed entering child with PadActivate not setting ActiveIdSource to Nav (#323)

Nav: Hovering MenuItem/Selectable with mouse makes NavId, matching what seems to be Windows beahvior at least for menus (#323)

Nav: Mouse pos passed to backend always rounded, so that lossy application of non-integer mouse pos doesn't lead to undesirable movement (#3

Nav: Clearing mouse hover flag using MouseClicked[] test instead of MouseDown[] so that invalid mouse button won't keep breaking nav (#323)

Nav: Tidying up. Comments. (#323)

Nav: Fixed a bug where mouse positioning requests would be sent while opening submenus with mouse (#323)

Nav: Comments + fixed handling of PadLeft in menus (fix e55882f) (#323)

Renamed function (#323)

Metrics: 64-bit display fix

Nav: NavHighlight gets its own color (default to Header color), made rectangle thicker (#323)

Nav: Exposed RenderNavHighlight() in imgui_internal.h to increase discoverability and reordered arguments to be more consistent (#323)

Nav: Fixed clipping rect of navigation highlight, notably for collapsing arrow (#323)

InputText: Fixed calling callback on frame of losing active id, fix part of 848e62b (nav branch only) ...

#323 #701

Merge branch 'master' into 2016-07-navigation

Minor shuffle to ease merging branches. (tentative. fugly but those fields will be removed anyway)

Minor shuffle to ease merging branches.

Nav: DragBehavior: Adjust minimum step to displayed precision when using navigation (#323, #180)

Nav: DragBehavior: Fix for fast speed (#323 #180)

Selectable/MenuItem: Not activated on Click but only on Release is more standard (#126, #245, #323) ...

Apparently menu items started with OnClick (vs OnClickHoldRelease) when
doing #126. Hope to not break anything.
Also allows using xxx_DontClosePopup flags.

Refactored rare transient bool stacks into a set of flags, added unexposed ImGuiItemFlags_SelectableDontClosePopup (#323)

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)