update config

config.moon

@@ -1,13 +1,5 @@
 config = require "lapis.config"
 
-ffi = actualrequire("ffi")
-ffi.cdef [[
-  char *getenv(const char *name)
-]]
-
-getenv = (name) ->
-  ffi.string ffi.C.getenv name
-
 config "development", ->
   port 8080
 
@@ -23,8 +15,8 @@ config "docker", ->
 
   postgres ->
     backend "pgmoon"
-    port getenv "POSTGRESQL_PORT_5432_TCP_PORT"
-    host getenv "POSTGRESQL_PORT_5432_TCP_ADDR"
-    user getenv "DB_USER"
-    password getenv "DB_PASS"
-    database getenv "DB_NAME"
+    port tostring os.getenv "POSTGRESQL_PORT_5432_TCP_PORT"
+    host tostring os.getenv "POSTGRESQL_PORT_5432_TCP_ADDR"
+    user tostring os.getenv "DB_USER"
+    password tostring os.getenv "DB_PASS"
+    database tostring os.getenv "DB_NAME"