Created Upgrading (markdown)
Updated Self Hosting (markdown)
WIP upgrading from v3 to v4
Updated Elasticsearch setup guide (markdown)
Corrected url for "replace the existing IExceptionFilter" link
Corrected url for "error response to include the Reference Id" anchor
Corrected url for WebHookData samples
Added docker container installation instructions
removed jdk requirement for production, lowered IIS version to min 7.5
Updated Project Settings (markdown)
raygun supports sending custom data
Updated Versioning (markdown)