Update .travis.yml

Trying to download and build GLFW since APT repository are unreliable

Update .travis.yml PPA source for glfw in the end of getting a newer version of GLFW

Examples: Mouse cursor handling comments/tweaks to homogenize. (#1495)

Examples: GLFW: Added support for mouse cursors (ImGui::GetMouseCursor() value and WM_SETCURSOR message handling). (#1495)

Examples: GLFW*: Renamed GLFW callbacks exposed in .h to not include GL2/GL3/Vulkan in their name.

Examples: DirectX 9,10,11: Inputs: Added support for mouse cursors (ImGui::GetMouseCursor() value and WM_SETCURSOR message handling). (#1495)

Update Breaking Change section with moved misc/fonts/ (#1631)

FAQ about backslashes in string literal since the one in main.cpp isn't being noticed enough. (#1397)

Initialization happens during CreateContext(), which makes it easier for platform layers to interact with the context during their initialization.

Merged a bunch of small inconsequential things from my work branch, to reduce the diff noise.

Nav: Tweak windowing highlighting for full viewport windows.

Examples: GLFW+GL2/GL3: Added glPixelStorei() calls borrowed from SDL examples.

Examples: Renamed .sln file.

Examples: Vulkan: Fix for empty draw data (init time) + fixed warning.

Examples: Vulkan: Added .vcproj files.

Examples: SDL: Fixed minor warning.

Examples: SDL: Added .vcproj files.

Examples: SDL: Minor stylistic tweaks. Fixed handling of ImGuiMouseCursor_None so it doesn't underflow array. Fixed harmless uninitialized pointer. (#1626)

Renamed misleading ImGuiMouseCursor_Move to ImGuiMouseCursor_ResizeAll. SDL: Fixed cursor. (#1626)

Use SDL system cursors in SDL examples. (#1626) ...

(Squashed 4 commits)

Obsoleted the io.RenderDrawListsFn callback, you can call your graphics engine render function after ImGui::Render(). Use ImGui::GetDrawData() to retrieve the ImDrawData* to display..(#1599) ...

Examples: Updated examples.

Examples: Added Changelog to make updates easier.

Fixed GCC zealous warnings (#1623)

Plot: plot a flat line if scale_min==scale_max (#1621)

Updated to stb_truetype 1.19 (include minor fix for #1622)

Examples: SDL: Added Changelog at the top of the imgui_impl files. (#1618)

ImFont: stb_truetype now rounding Ascent/Descent the same way as freetype does, they seem to vertically align better this way.

ImFont: DisplayOffset.y defaults to 0 instead of +1.

Update README.md