Add var for number of seconds between data refreshes. Rename locals file to config and also end example files in .dart.

lib/var/config.EXAMPLE.dart

@@ -0,0 +1,5 @@
+// This file needs renamed `local.dart` when implemented.
+
+// Project-wide configuration variables for both testing and production.
+const bool debug = false;
+const int limitRefreshSeconds = 60;

lib/var/locals.dart.EXAMPLE

@@ -1,3 +0,0 @@
-// This file needs renamed `local.dart` if implemented.
-
-const bool debug = false;

lib/var/secrets.EXAMPLE.dart

@@ -1,3 +1,3 @@
 // This file needs renamed `secrets.dart` and filled out properly if implemented.
 
-final openWeatherKey = "abc123";
+final String openWeatherKey = "abc123";