traits documentation - Make it clear how to specify 2 or more options

[davsclaus]

You need --trait for each parameter, so it gets a bit verbose

kamel run hello.xml --trait container.request-memory=50Mi --trait container.limit-memory=100Mi

The documentation only shows

kamel run --trait container.[key]=[value] integration.groovy

We could maybe update the auto generated docs to include a section about multiple configurations

kamel run --trait container.[key]=[value] --trait container.[key2]=[value2] integration.groovy