matchingPrecedence is used to choose among the FlowSchemas that match a given request.
The chosen FlowSchema is among those with the numerically lowest (which we take to be logically highest) MatchingPrecedence.
Each MatchingPrecedence value must be ranged in 1,10000.
Note that if the precedence is not specified, it will be set to 1000 as default.
rules describes which requests will match this flow schema.
This FlowSchema matches a request if and only if at least one member of rules matches the request.
if it is an empty slice, there will be no requests matching the FlowSchema.
FlowSchemaSpec describes how the FlowSchema's specification looks like.