WebSearch: add bibdocs to record context
sqlalchmeyutils: fix missing database host port

* Database connections setup via SQLAlchemy did not use
  CFG_DATABASE_PORT, meaning that connections could only be made to
  database hosts running on standard ports.
WebStyle: fix stdout redirect for mod_wsgi and shell

* Due to module dependencies webinterface_handler_wsgi is loaded
  even for Invenio CLI commands, meaning that stdout is redirect
  to stderr. This fix moves the redirect from the WSGI handler to the
  WSGI script.
WebSearch: add download graph to record blueprint

* Add download graph to template context to match functionality
  of previous Invenio versions.
InvenioUpgrader: partial fix for SQLAlchemy init

* InvenioUpgrader imports pluginutils which imports webinterface_handler
  which in the end results in an SQLAlchemy model being imported. The model
  then raises an exception due to the SQLAlchemy engine not being initialized.
  This partial fix ensures the engine is initialized by loading
  invenio.flaskshell. However, 'make check-upgrade' will not work for
  non-SQLAlchemy based installations, but will nonetheless report this.