Fix exposing abs_url_for to templates

app/template_filters.py

@@ -1,10 +1,16 @@
 from . import app
+from .utils import abs_url_for
 from urllib.parse import urlparse
 
 @app.context_processor
 def inject_debug():
     return dict(debug=app.debug)
 
+
+@app.context_processor
+def inject_functions():
+    return dict(abs_url_for=abs_url_for)
+
 @app.template_filter()
 def throw(err):
 	raise Exception(err)