Endpoint for issuing Event notification to ConfigService

[baardl]

Suggestion: PUT /client/{clientId}/event

Reasoning:
During upgrade of Java-auto-update,ConfigService will have to programatically determine which ApplicationConfiguration a spesific client needs. The decision will be made based on a specific event received from either JAU or MJAUU.
We should avoid having to parse the log-events received in sync messages, in order to interpret the specific events received. A preferred technique is to provide a unique endpoint for creating an event:

PUT /client/{clientId}/event - body = Extension to Event?

Another challenge today is that Event is very log-line-specific, though. Please see suggestion on #44

What I try to accomplish is support for this: https://wiki.cantara.no/display/JAU/MJAUU+-+My+JAU+Updater+(Update+the+Java-Auto-Update+itself+)#MJAUU-MyJAUUpdater%28UpdatetheJava-Auto-Updateitself%29-MJAUUStateandEvents