Add support for multiple dashboards.

Add support for removing dashboard widgets.

Signed-off-by: Roberto Rosario <roberto.rosario.gonzalez@gmail.com>

mayan/apps/common/mixins.py

@@ -6,7 +6,6 @@ from django.core.exceptions import PermissionDenied
 from django.db.models.query import QuerySet
 from django.http import HttpResponseRedirect
 from django.shortcuts import resolve_url
-from django.urls import reverse
 from django.utils.translation import ungettext, ugettext_lazy as _
 
 from permissions import Permission