Provide global_settings and user_settings as context objects

- Adds a new context middleware
- Refactor the way that settings are provided to the javascript layer

InvenTree/part/templatetags/inventree_extras.py

@@ -6,6 +6,7 @@ over and above the built-in Django tags.
 
 import os
 import sys
+from django.utils.html import format_html
 
 from django.utils.translation import ugettext_lazy as _
 from django.conf import settings as djangosettings
@@ -208,24 +209,6 @@ def settings_value(key, *args, **kwargs):
     return InvenTreeSetting.get_setting(key)
 
 
-@register.simple_tag()
-def user_settings(user, *args, **kwargs):
-    """
-    Return all USER settings as a key:value dict
-    """
-
-    return InvenTreeUserSetting.allValues(user=user)
-
-
-@register.simple_tag()
-def global_settings(*args, **kwargs):
-    """
-    Return all GLOBAL InvenTree settings as a key:value dict
-    """
-
-    return InvenTreeSetting.allValues()
-
-
 @register.simple_tag()
 def get_color_theme_css(username):
     try:
@@ -262,6 +245,25 @@ def get_available_themes(*args, **kwargs):
     return themes
 
 
+@register.simple_tag()
+def primitive_to_javascript(primitive):
+    """
+    Convert a python primitive to a javascript primitive.
+
+    e.g. True -> true
+         'hello' -> '"hello"'
+    """
+
+    if type(primitive) is bool:
+        return str(primitive).lower()
+
+    elif type(primitive) in [int, float]:
+        return primitive
+
+    else:
+        # Wrap with quotes
+        return format_html("'{}'", primitive)
+
 @register.filter
 def keyvalue(dict, key):
     """