added fluent .properties, fix/add fluent unit tests

[304NotModified]

• added .properties for the fluent builder.

            var props = new Dictionary<string, object>
            {
                {"prop1", "1"},
                {"prop2", "2"},

            };

            _logger.Trace()
                .Message("This is a test fluent message.")
                .Properties(props).Write();

• improved loggingRule docs
• fix the unit tests for the Logbuilder.
• fix sync unit test projects for silverlight5

Fixes #724, fixes #911

[304NotModified]

Has unit test, but not a good one. See #911