Tweak fckeditor.py to support WSGI

[whit537]

The fckeditor.py module assumes a CGI environment by hardwiring os.environ into FCKeditor.IsCompatible. The attached patch adds an Environ attribute to the class, which, if set after instantiation but before Create is called, will be used instead of os.environ. This allows the caller to use the module in a long running process, for example, by substituting a WSGI environ for the CGI environ.