glfw: Update GLFW to current master

glfw/glfw@5595fa3ae6 implements a proper fix for the macOS Mojave
problem of OpenGL windows not being rendered until moved or manually
updated.

Pull in the current master and rebase the three patches we have on top:
- two commits we have for reuse of the GLFW CMake build system for Wayland
It hasn't yet to be acknowledged upstream.
- one commit removing #include <windows.h> in glfw3native.h to avoid
duplicate declarations.

Fixes #655 and #665.

src/external/glfw/README.md

@@ -11,8 +11,8 @@ application development.  It provides a simple, platform-independent API for
 creating windows, contexts and surfaces, reading input, handling events, etc.
 
 GLFW natively supports Windows, macOS and Linux and other Unix-like systems.
-Experimental implementations for the Wayland protocol and the Mir display server
-are available but not yet officially supported.
+An experimental implementation for the Wayland protocol is available but not
+yet officially supported.
 
 GLFW is licensed under the [zlib/libpng
 license](http://www.glfw.org/license.html).
@@ -167,6 +167,8 @@ information on what to include when reporting a bug.
   (#749,#842)
 - Added `GLFW_FOCUS_ON_SHOW` window hint and attribute to control input focus
   on calling show window (#1189)
+- Added `GLFW_SCALE_TO_MONITOR` window hint for automatic window resizing
+  (#676,#1115)
 - Added `GLFW_JOYSTICK_HAT_BUTTONS` init hint (#889)
 - Added `GLFW_LOCK_KEY_MODS` input mode and `GLFW_MOD_*_LOCK` mod bits (#946)
 - Added macOS specific `GLFW_COCOA_RETINA_FRAMEBUFFER` window hint
@@ -180,6 +182,10 @@ information on what to include when reporting a bug.
 - Added `GLFW_OSMESA_CONTEXT_API` for creating OpenGL contexts with
   [OSMesa](https://www.mesa3d.org/osmesa.html) (#281)
 - Added `GenerateMappings.cmake` script for updating gamepad mappings
+- Export CMake `GLFW_PKG_DEPS` and `GLFW_PKG_LIBS` to parent scope for use
+  in client pkg-configs (#1307)
+- Added a `glfw_objlib` CMake OBJECT library target for embedding into static
+  libraries (#1307)
 - Made `glfwCreateWindowSurface` emit an error when the window has a context
   (#1194,#1205)
 - Deprecated window parameter of clipboard string functions
@@ -195,6 +201,8 @@ information on what to include when reporting a bug.
 - Bugfix: Invalid library paths were used in test and example CMake files (#930)
 - Bugfix: The scancode for synthetic key release events was always zero
 - Bugfix: The generated Doxyfile did not handle paths with spaces (#1081)
+- Bugfix: The gamma ramp generated by `glfwSetGamma` did not use the monitor
+          ramp size (#1387,#1388)
 - [Win32] Added system error strings to relevant GLFW error descriptions (#733)
 - [Win32] Moved to `WM_INPUT` for disabled cursor mode motion input (#125)
 - [Win32] Removed XInput circular deadzone from joystick axis data (#1045)
@@ -221,6 +229,10 @@ information on what to include when reporting a bug.
 - [Win32] Bugfix: The HID device notification was not unregistered (#1170)
 - [Win32] Bugfix: `glfwCreateWindow` activated window even with `GLFW_FOCUSED`
                   hint set to false (#1179,#1180)
+- [Win32] Bugfix: The keypad equals key was reported as `GLFW_KEY_UNKNOWN`
+                  (#1315,#1316)
+- [Win32] Bugfix: A title bar would be drawn over undecorated windows in some
+                  circumstances (#1383)
 - [X11] Moved to XI2 `XI_RawMotion` for disable cursor mode motion input (#125)
 - [X11] Replaced `_GLFW_HAS_XF86VM` compile-time option with dynamic loading
 - [X11] Bugfix: `glfwGetVideoMode` would segfault on Cygwin/X
@@ -235,6 +247,8 @@ information on what to include when reporting a bug.
 - [X11] Bugfix: Selection I/O reported but did not support `COMPOUND_TEXT`
 - [X11] Bugfix: Latin-1 text read from selections was not converted to UTF-8
 - [X11] Bugfix: NVidia EGL would segfault if unloaded before closing the display
+- [X11] Bugfix: Checking window maximized attrib could crash some WMs (#1356)
+- [X11] Bugfix: Update cursor position on enter event (#1366)
 - [Linux] Added workaround for missing `SYN_DROPPED` in pre-2.6.39 kernel
           headers (#1196)
 - [Linux] Moved to evdev for joystick input (#906,#1005)
@@ -267,6 +281,9 @@ information on what to include when reporting a bug.
 - [Cocoa] Bugfix: Window was resized twice when entering full screen (#1085)
 - [Cocoa] Bugfix: Duplicate size events were not filtered (#1085)
 - [Cocoa] Bugfix: Event polling did not initialize AppKit if necessary (#1218)
+- [Cocoa] Bugfix: OpenGL rendering was not initially visible on 10.14
+                  (#1334,#1346)
+- [Cocoa] Bugfix: Caps Lock did not generate any key events (#1368,#1373)
 - [WGL] Added support for `WGL_EXT_colorspace` for OpenGL ES contexts
 - [WGL] Added support for `WGL_ARB_create_context_no_error`
 - [GLX] Added support for `GLX_ARB_create_context_no_error`
@@ -304,7 +321,9 @@ skills.
  - David Avedissian
  - Keith Bauer
  - John Bartholomew
+ - Coşku Baş
  - Niklas Behrens
+ - Andrew Belt
  - Niklas Bergström
  - Denis Bernard
  - Doug Binks
@@ -371,6 +390,7 @@ skills.
  - Glenn Lewis
  - Shane Liesegang
  - Eyal Lotem
+ - Aaron Loucks
  - Tristam MacDonald
  - Hans Mackowiak
  - Дмитри Малышев
@@ -387,6 +407,7 @@ skills.
  - Bruce Mitchener
  - Jack Moffitt
  - Jeff Molofee
+ - Alexander Monakov
  - Pierre Morel
  - Jon Morton
  - Pierre Moulon