plugin to use MongoDB as backend.

tested in ubuntu 10.04 and ubuntu 10.10

configuration:

in your /etc/rsyslog.conf, together with other modules:
$ModLoad ommongodb # provides mongodb support
*.*     action(type="ommongodb" db="..." collection="..." template="...")

Note: if no template is specified, a default schema will be used. That schema
contains proper data types. However, if a template is specified, only strings
are supported. This is a restriction of the rsyslog v6 core engine. This 
changed in v7.

If templates are used, it is suggested to use list-based templates. Constants
can ONLY be inserted with list-based templates, as only these provide the
capability to specify a field name (outname parameter).
