GIT-INFO: convert to markdown

Closes #13074

GIT-INFO.md

@@ -0,0 +1,42 @@
+                                  _   _ ____  _
+                              ___| | | |  _ \| |
+                             / __| | | | |_) | |
+                            | (__| |_| |  _ <| |___
+                             \___|\___/|_| \_\_____|
+
+# GIT-INFO
+
+This file is only present in git - never in release archives. It contains
+information about other files and things that the git repository keeps in its
+inner sanctum.
+
+To build in environments that support configure, after having extracted
+everything from git, do this:
+
+    autoreconf -fi
+    ./configure --with-openssl
+    make
+
+Daniel uses a configure line similar to this for easier development:
+
+    ./configure --disable-shared --enable-debug --enable-maintainer-mode
+
+In environments that don't support configure (i.e. Windows), do this:
+
+    buildconf.bat
+
+## REQUIREMENTS
+
+For `autoreconf` and `configure` (not `buildconf.bat`) to work, you need the
+following software installed:
+
+ o autoconf 2.57  (or later)
+ o automake 1.7   (or later)
+ o libtool  1.4.2 (or later)
+ o GNU m4 (required by autoconf)
+ o perl
+
+If you don't have perl and don't want to install it, you can rename the source
+file `src/tool_hugehelp.c.cvs` to `src/tool_hugehelp.c` and avoid having to
+generate this file. This will give you a stubbed version of the file that
+doesn't contain actual content.