Improve config system

Add pkl to generate configs

config/lib/common.pkl

@@ -0,0 +1,15 @@
+class ServerConfig {
+	host: String
+	port: UInt16
+}
+
+/// Set to a user and a group to drop privileges to after binding to the port
+class PermissionsConfig {
+	user: String
+	group: String
+}
+
+class LoggingConfig {
+	level: String
+	file: String
+}

config/lib/controller.pkl

@@ -0,0 +1,16 @@
+import "./common.pkl"
+
+server: common.ServerConfig
+
+database: String
+
+permissions: common.PermissionsConfig
+
+logging: common.LoggingConfig
+
+class RelayConfig {
+	driver: "gpio" | "piface"
+	pin: Number
+	inverted: Boolean
+}
+relays: Listing<RelayConfig>

config/lib/core.pkl

@@ -0,0 +1,12 @@
+import "./common.pkl"
+
+server: common.ServerConfig
+
+database: String
+
+permissions: common.PermissionsConfig
+
+logging: common.LoggingConfig
+
+/// Leave empty to allow all origins (will always respond with Origin and not "*")
+origins: Listing<String>