[datafeed] also catch EnvironmentError when trying to load the cwclientlib config file
means the config file has not been found, so fall back to the old implementation
instead of crashing.
Document: cubicweb-doc
Title: CubicWeb documentation
Author: Logilab
Abstract: Some base documentation for CubicWeb users and developpers
Section: Apps/Programming
Format: HTML
Index: /usr/share/doc/cubicweb-documentation/index.html
Files: /usr/share/doc/cubicweb-documentation/*.html