implement game configuration file

this integrates https://github.com/cktan/tomlc99 into the repo as a dependency

third-party/tomlc99/libtoml.pc.sample

@@ -0,0 +1,11 @@
+prefix=/usr/local
+exec_prefix=${prefix}
+libdir=${exec_prefix}/lib
+includedir=${prefix}/include
+
+Name: libtoml
+URL: https://github.com/cktan/tomlc99/
+Description: TOML C library in c99.
+Version: v1.0
+Libs: -L${libdir} -ltoml
+Cflags: -I${includedir}