implement game configuration file

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

data/twn.toml

@@ -0,0 +1,27 @@
+# This file contains everything about the engine and your game that can be
+# configured before it runs.
+#
+# Optional settings are commented out, with their default values shown.
+# Invalid values in these settings will be ignored.
+
+# Data about your game as an application
+[about]
+title = "It's TownEngine!"
+developer = "Somebody"
+app_id = "townengine"
+dev_id = "somebody"
+
+# Game runtime details
+[game]
+base_render_width = 640
+base_render_height = 360
+#debug = true
+
+# Engine tweaks. You probably don't need to change these
+[engine]
+#ticks_per_second = 60 # minimum of 8
+#keybind_slots = 3 # minimum of 1
+#texture_atlas_size = 2048 # minimum of 32
+#font_texture_size = 2048 # minimum of 1024
+#font_oversampling = 4 # minimum of 0
+#font_filtering = "linear" # possible values: "nearest", "linear"