If LogName contains "." no custom log table will be created in Azure

[ConnorCallison]

Describe the bug I had tried to have my LogNames match my project names eg: MyProject.WebApp, and no log tables were showing up in Azure Log Analytics. After a while I removed the logName parameter and the default log table was created immediately. I then swapped out the "." for an "_" and all was created as expected.

To Reproduce

1. Set log name to something like "MyProject.ProjectName" and run your application to generate some log entries.
2. Open up azure Log analytics and no log table will be created.

Expected behavior I think we should add a note to the xml documentation comment about valid characters for log names and / or have the sink replace all periods in the LogName with underscores.

[ConnorCallison]

Created a pull request here - https://github.com/saleem-mirza/serilog-sinks-azure-analytics/pull/53