addMixin(String aspectClass, DeploymentModel deploymentModel, String pointcut, boolean isTransient) Creates and adds a new mixin builder to the deployment set.
Creates, registers and returns an aspect definition builder.
Use-case: Get an aspect builder and then use it to add advice and pointcut builders to build up a full aspect
definintion programatically.
Parameters: aspectClass - Parameters: scope - Parameters: containerClassName - a newly registered aspect builder