Merge various minor things (supposedly harmless) from Navigation branch into Master to reduce differences. (#787)

RenderRectFilledRangeH() can't use cheap acosf() approximation for now. (#1296)

ProgressBar() fixed rendering when straddling rounded area. (#1296)

Added overcomplicated RenderRectFilledRangeH() to fix rounded progress bar, which will also help for range widgets and perhaps sliders grabs over rounded areas. (#1296, #76)

ImDrawList: Minor renaming

ImSwap() helper.

imDrawList: PathArcTo() returns when passed zero radius.

ImDrawList: Minor tidying up.

Internals: Renamed some ImGuiCorner enums.

ParseFormatPrecision() returns -1 for scientific noation 'e'/'E', RoundScalar() doesn't alter those.

Added Go binding link

Updated copyright date for 2017, updated Gallery link

Internals: Split some code out of NewFrame() into an Initialize() function.

Added IsMousePosValid() helper.

ImFontConfig: Added RasterizerMultiply option to alter the brightness of individual fonts at rasterization time, which may help increasing readability for some. Added RasterizerFlags for custom rasterizer flags (aka imgui_freetype)

ImFontConfig: Comments, const.

Fixed compilation with IMGUI_DISABLE_OBSOLETE_FUNCTIONS defined

IO: io.MousePos needs to be set to ImVec2(-FLT_MAX,-FLT_MAX) when mouse is unavailable/missing. Previously ImVec2(-1,-1) was enough but we'll now accept negative mouse coordinates.

Marked all fmt + va_list functions with format attribute so GCC/Clang can warn about them. Not ignoring -Wsuggest-attribute=format anymore for GCC/Clang.

Version 1.52 WIP

Version 1.51

Demo: Displaying version number in test window.

Style: Tweaked default border (undo half-way from original c1e1e01) (#707)

Minor miscellaneous merges from Navigation branch to reduce divergence a little bit

Renamed IsItemHoveredRect() to IsItemRectHovered(). Renamed IsMouseHoveringWindow() to IsWindowRectHovered() - follow up to previous commit 6be7d49 merged from Nav.

Style: Added obsolete redirects for ImGuiCol_Columns*** fields. (ref 648f75b)

Merge part of 88c1966 from Nav branch. Renamed IsMouseHoveringAnyWindow() -> IsAnyWindowHovered(), IsMouseHoveringWindow() -> IsWindowHoveredRect() for consistency. Kept inline rediection function.

(internals) Renamed FocusedWindow to NavWindow to match terminology of navigation branch

Merge 20a0fde Tidying up default clipboard handler for non Windows-OS (from Nav branch)

Merge 2545d75 from Nav - Tidying up, removed two unnecessary window flags from being exposed in imgui.h