Disable sendfile when running dev from vagrant.

Upgrade gunicorn.
Add BS3 classes to rendered markdown tables. Fixes #72

realms/config/__init__.py

@@ -1,7 +1,7 @@
 import os
 import json
 from urlparse import urlparse
-
+from realms.lib.util import in_vagrant
 
 def update(data):
     conf = read()
@@ -152,6 +152,10 @@ SQLALCHEMY_DATABASE_URI = DB_URI
 _url = urlparse(BASE_URL)
 RELATIVE_PATH = _url.path
 
+if in_vagrant():
+    # sendfile doesn't work well with Virtualbox shared folders
+    USE_X_SENDFILE = False
+
 if ENV != "DEV":
     DEBUG = False
     ASSETS_DEBUG = False