Merge remote-tracking branch 'origin' into 2016-02-colorpicker

Columns: First first column appearing wider than others (#1266)

SetScrollHere() tweak to make the code a little less confusing

Fixed Y scroll aiming when Horizontal Scrollbar is enabled (#665). Tweak log demo.

Fixes for Vertical Scrollbar not automatically getting enabled if enabled Horizontal Scrollbar straddle the vertical limit. (#1271, #246)

Fixed GetScrollMaxX(), GetScrollMaxY(). Tweak demo to display more data. Using functions in Begin(). (#1271)

Fonts readme tweaks, links

Moved ColorEdit, ColorPicker declaration in their own section of imgui.h, minor comments adjustment (#346)

Demo: Comment about 'static' and some tweaks (#1267)

Popups window can be moved (if they don't have explicit positions provided by user, or e.g. sub-menu popup) (#1252)

Comments, clarification about io.WantCaptureMouse, io.WantCaptureKeyboard flags timing and NewFrame(). (#1262)

Clipboard: [windows] Fixed not closing win32 clipboard on early return. (#1264)

DataTypeApplyOpFromText: renamed local variables + comments to avoid confusion about the fact that int and float paths are not totally symetrical. (#671)

ColorPicker: Hue wheel + SV triangle picker mode (mode selection flags still wip, missing context menu and persistent options). (#346)

Internals: Added ImLineClosestPoint, ImTriangleClosestPoint helpers. Changing ImVec2 arg to const ImVec2&

Internals: Added ImDot(), ImRotate(), ImLerp(v2,v2,float) helpers.

Internals: Added ImTriangleBarycentricCoords() helper. Renamed ImIsPointInTriangle() to ImTriangleContainsPoint(), with different arg order.

ColorEdit: Extract ColorOptionsPopup() function out of ColorEdit4(). (#346)

ColorPicker: Rearrange code to introduce alternate HSV picker/selector with simpler diff. (#346)

Comments, minor tidying up.

Use ~IM_COL32_A_MASK instead of IM_COL32(255,255,255,0)

ColorPicker: Reordered drawing code to match left-to-right display. Extra comments. (#346)

Renamed ImGuiColorEditFlags_ModeMask_ to ImGuiColorEditFlags_InputsModeMask_ (#346)

ColorPicker4: Fixed forwarding _HDR flag from ColorPicker4 back to ColorEdit4 components. (#346)

ColorPicker: Alpha bar using a checkerboard. (#346)

ColorEdit4: Preliminary support for ImGuiColorEditFlags_HDR flag (currently only lift limits). (#346)

ColorEdit4: Hex input clamps integer components to 0..255 range during printout (#346)

Demo: Tweaks

ColorButton: Added frame border when style border are off. (#346) @jdumas

ImGuiColorEditFlags: Made 0x01 unused for backward compatibility with old bool. Various comments tweaks. (#346)