Add 'settings.js' which provides all settings (global and user) as a dynamic javascript file

- Minimal database hits required

InvenTree/templates/js/dynamic/settings.js

@@ -0,0 +1,17 @@
+{% load inventree_extras %}
+// InvenTree settings
+
+{% user_settings request.user as USER_SETTINGS %}
+{% global_settings as GLOBAL_SETTINGS %}
+
+var user_settings = {
+    {% for setting in USER_SETTINGS %}
+    {{ setting.key }}: {{ setting.value }},
+    {% endfor %}
+};
+
+var global_settings = {
+    {% for setting in GLOBAL_SETTINGS %}
+    {{ setting.key }}: {{ setting.value }},
+    {% endfor %}
+};