docs: https all the links \o/

Most of them already redirected to https anyway, so we might as well
avoid the redirection and the security implications by linking directly
to the right protocol.

Signed-off-by: Eric Engestrom <eric@engestrom.ch>
Reviewed-by: Brian Paul <brianp@vmware.com>
diff --git a/docs/intro.html b/docs/intro.html
index f7e3728..d90d0cb 100644
--- a/docs/intro.html
+++ b/docs/intro.html
@@ -18,17 +18,17 @@
 
 <p>
 The Mesa project began as an open-source implementation of the
-<a href="http://www.opengl.org/">OpenGL</a> specification -
+<a href="https://www.opengl.org/">OpenGL</a> specification -
 a system for rendering interactive 3D graphics.
 </p>
 
 <p>
 Over the years the project has grown to implement more graphics APIs,
 including
-<a href="http://www.khronos.org/opengles/">OpenGL ES</a> (versions 1, 2, 3),
-<a href="http://www.khronos.org/opencl/">OpenCL</a>,
+<a href="https://www.khronos.org/opengles/">OpenGL ES</a> (versions 1, 2, 3),
+<a href="https://www.khronos.org/opencl/">OpenCL</a>,
 <a href="https://en.wikipedia.org/wiki/VDPAU">VDPAU</a> and
-<a href="http://www.khronos.org/vulkan/">Vulkan</a>.
+<a href="https://www.khronos.org/vulkan/">Vulkan</a>.
 </p>
 
 <p>
@@ -39,8 +39,8 @@
 
 <p>
 Mesa ties into several other open-source projects: the
-<a href="http://dri.freedesktop.org/">Direct Rendering
-Infrastructure</a> and <a href="http://x.org">X.org</a> to
+<a href="https://dri.freedesktop.org/">Direct Rendering
+Infrastructure</a> and <a href="https://x.org">X.org</a> to
 provide OpenGL support on Linux, FreeBSD and other operating
 systems.
 </p>
@@ -94,7 +94,7 @@
 1995-1996: I continue working on Mesa both during my spare time and during
 my work hours at the Space Science and Engineering Center at the University
 of Wisconsin in Madison.  My supervisor, Bill Hibbard, lets me do this because
-Mesa is now being using for the <a href="http://www.ssec.wisc.edu/%7Ebillh/vis.html">Vis5D</a> project.
+Mesa is now being using for the <a href="https://www.ssec.wisc.edu/%7Ebillh/vis.html">Vis5D</a> project.
 </p><p>
 October 1996: Mesa 2.0 is released.  It implements the OpenGL 1.1 specification.
 </p>
@@ -151,7 +151,7 @@
 
 <p>
 2008: Keith Whitwell and other Tungsten Graphics employees develop
-<a href="http://en.wikipedia.org/wiki/Gallium3D">Gallium</a>
+<a href="https://en.wikipedia.org/wiki/Gallium3D">Gallium</a>
 - a new GPU abstraction layer.  The latest Mesa drivers are based on
 Gallium and other APIs such as OpenVG are implemented on top of Gallium.
 </p>
@@ -279,7 +279,7 @@
 </pre>
 <p>
 See the
-<a href="http://www.opengl.org/documentation/spec.html">
+<a href="https://www.opengl.org/documentation/spec.html">
 OpenGL specification</a> for more details.
 </p>