Bugfixes in lodel/buildconf.py & mongodb plugin

configure.ac

 	AC_MSG_WARN([Module werkzeug not found but mandatory for default web interface])
 	AC_SUBST([WEBUI], 'False'))
 #Mongo datasource deps
-AC_SUBST([MONGODB], 'True') #Can be found in lodel/buildconf.py
+AC_SUBST([PYMONGO], 'True') #Can be found in lodel/buildconf.py
 PC_PYTHON_CHECK_MODULE([pymongo], ,
 	AC_MSG_WARN([Module pymongo not found. The mongodb datasource will not be able to work])
-	AC_SUBST([MONGODB], 'False'))
+	AC_SUBST([PYMONGO], 'False'))
 
 #Documentation checks
 AC_SUBST([DOCOK], 'OK')

lodel/buildconf.py.in

 ##@brief Stores constant evaluated at build time
 #@note Populated by ./configure
 
-PYMONGO=@MONGODB@
+PYMONGO=@PYMONGO@
 WEBUI=@WEBUI@

lodel/plugin/plugins.py

 import json
 from importlib.machinery import SourceFileLoader, SourcelessFileLoader
 
-import plugins
 from lodel import logger
 from lodel.settings.utils import SettingsError
 from .exceptions import *

plugins/mongodb_datasource/__init__.py

 #
 # @return bool|str : True if all the checks are OK, an error message if not
 def _activate():
-    return True
+    from lodel import buildconf
+    return buildconf.PYMONGO