implement game configuration file

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

third-party/tomlc99/stdex/string1.toml.res

@@ -0,0 +1,5 @@
+{
+  str1 = "Roses are red\nViolets are blue",
+  str2 = "Roses are red\nViolets are blue",
+  str3 = "Roses are red\r\nViolets are blue",
+}