[MNG-5668] Proof of concept implementation of dynamic phases (wip)

[gnodet]

The lifecycle is defined as a tree, of phases, each phase being split with a pre: phase and a post: phase. Each phase is given a list of timing constraints: a phase from the same lifecycle (compile must be executed after sources), a phase in project dependencies (compile must execute after compile-only project dependencies have reached the ready phase), or a set of children project dependencies (to re-define aggregators, not yet implemented).
The default lifecycle is defined in the DefaultLifecycleRegistry

Note that there are a few changes with the Maven 3 default lifecycle: it's a graph, so sources does not always execute after resources, not compile after resources. Also, unit tests and integration tests have been moved to the verify phase which is run last inside the build phase, but not in the package phase. The goal is to have a phase (here, package which can run all the reactor with no tests). In order to be compatible, old phases are mapped to new ones using aliases.

It's missing the ability to create some scheduling constraints in the POM and to define custom phases. All executions in a give phase such as compile or process-sources are executed sequentially, but it would be nice to be able to execute them in different subphases, so that they could be executed concurrently.

WIP, related to #1411 and #1429