* Previously, there would always be a "close window" button in the corner, because internally ImGui.cs was passing a non-null pointer to the underlying function. Now, it only does so if you call an overload with the "ref bool" parameter.
* igCollapsingHeader (3-params) renamed to igCollapsingHeaderEx.
* igColor and igColor2 removed -- they no longer exist in cimgui.
* igBeginMenu (1-param) removed. igBegin is already imported, and it has
two parameters, not one.
* Fixed two typos in DrawList function names.
* The drawlist branch includes a bunch of additional wrapper methods for
ImDrawList stuff. As part of that, the DrawList type had some minor
refactoring to it, in a way that closely mirrors other native types.
There is now a "managed" DrawList type, and a "raw" NativeDrawList type.
The DrawList type is a safe convenience wrapper over the native type,
which is still there if needed. Not all ImDrawList functions have
convenience wrappers yet, but there are enough to build quite a few
things with.
* This is also a fairly large reorganization and updating of the build files in
the repository. Given that a stable version of the .NET Core tools have
been release, I've updated all of the project files to use the new
project syntax exclusively. There is now only one project for ImGui,
which targets .NET Standard 1.1 using the new SDK syntax. There is a
single sample project as well, targeting .NET Core 1.0. .NET Framework
is still supported, because the library still targets .NET Standard 1.1.