implement game configuration file

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

third-party/tomlc99/stdex/tab04.toml

@@ -0,0 +1,6 @@
+# [x] you
+# [x.y] don't
+# [x.y.z] need these
+[x.y.z.w] # for this to work
+
+[x] # defining a super-table afterward is ok