Added a couple more HttpRequest* Enrichers

Contains Client IP, -Hostname, User Agent, (Raw) Url, Referrer and
Request Type. Never hurts to have a little extra options and info at
hand.
Updated HttpRequestClientHostIPEnricher to also check for proxies, if available
Fixed typo in code comment. meh.
Added option to en-/disable HTTP Proxy Check
Reintroduced fix from https://github.com/continuousit/seq-client/pull/19 dropped in project move
Merge branch 'master' of https://github.com/jbattermann/serilog into jbattermann-master
Merge branch 'jbattermann-master'
Merge branch 'master' of https://github.com/mcintyre321/serilog into mcintyre321-master
Couple of minor tweaks to keep R# happy, provide batching for other AzureTableStorageSink overload.
Merge branch 'mcintyre321-master'
Picked up a couple of ReSharper warnings in Serilog.Sinks.Splunk.
Added basic HTTP authentication support to the CouchDB sink.
Improved the handling of the authentication parameters on the CouchDB sink.
Removed old pre spec ready for GA release
#207: Fixed typo
Updated to match GA release
Revert "Removed old pre spec ready for GA release"

This reverts commit a3e27e3b682db0591953ba7f147adacdb7f739bd.
Merge remote-tracking branch 'origin/master'
Corrected issue with NuGet package update
#210: Added missing format placeholder