add a lib for rendering text in sdl2 and rules to make in makefile

SDL2_ttf/external/harfbuzz/BUILD.md

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+On Linux, install the development packages for FreeType, Cairo, and GLib. For
+example, on Ubuntu / Debian, you would do:
+
+$ sudo apt-get install meson pkg-config ragel gtk-doc-tools gcc g++ libfreetype6-dev libglib2.0-dev libcairo2-dev
+
+whereas on Fedora, RHEL, CentOS, and other Red Hat based systems you would do:
+
+$ sudo dnf install meson pkgconfig gtk-doc gcc gcc-c++ freetype-devel glib2-devel cairo-devel
+
+and on ArchLinux and Manjaro:
+
+$ sudo pacman -Suy meson pkg-config ragel gcc freetype2 glib2 cairo
+
+then use meson to build the project like `meson build && meson test -Cbuild`.
+
+On macOS, `brew install pkg-config ragel gtk-doc freetype glib cairo meson`
+then use meson like above.
+
+On Windows, meson can build the project like above if a working MSVC's cl.exe
+(`vcvarsall.bat`) or gcc/clang is already on your path, and if you use
+something like `meson build --wrap-mode=default` it fetches and compiles most
+of the dependencies also.  It is recommended to install CMake either manually
+or via the Visual Studio installer when building with MSVC, using meson.
+
+Our CI configurations is also a good source of learning how to build HarfBuzz.
+
+There is also amalgam source provided with HarfBuzz which reduces whole process
+of building HarfBuzz like `g++ src/harfbuzz.cc -fno-exceptions` but there is
+not guarantee provided with buildability and reliability of features you get.