Implement encryption_enabled_by_default_for_room_type. (closes #29)

Signed-off-by: Jason Volk <jason@zemos.net>

tuwunel-example.toml

@@ -459,6 +459,17 @@
 #
 #allow_encryption = true
 
+# Controls whether locally-created rooms should be end-to-end encrypted by
+# default. This option is equivalent to the one found in Synapse.
+#
+# Options:
+# - "all": All created rooms are encrypted.
+# - "invite": Any room created with `private_chat` or
+#   `trusted_private_chat` presets.
+# - Other values default to no effect.
+#
+#encryption_enabled_by_default_for_room_type = false
+
 # Controls whether federation is allowed or not. It is not recommended to
 # disable this after installation due to potential federation breakage but
 # this is technically not a permanent setting.