First, `rootDirectory` is nullable, CLIng code was not assuming this, fixed.
Second, emit the "no root found" warning ONLY when appropriate (when we have a POM in picture).
---
https://issues.apache.org/jira/browse/MNG-8302
Implements the `mvnenc` tool that is on par with Maven3 master password encryption functionality wise, but is _really secure_ unlike Maven3 conterpart. On the other hand, _is backward compatible if legacy config is setup_.
Implemented goals: `init`, `encrypt`, `decrypt`, `diag`. Also provides one extra "master source" based on Maven infra Prompter: console master password prompt.
---
https://issues.apache.org/jira/browse/MNG-8285
Changes:
* there is only one parser for "just maven", no need for 3
* aligned scopes (public) of local context for simplicity, we can fix visibility later
* allow custom guice modules (unused, may undo this)
* split logging setup in two steps: config and activate
---
https://issues.apache.org/jira/browse/MNG-8283
This PR adopts CLIng for use in mvnd, and adds several improvements to CLIng overall.
Major topics:
* ability to pass in per-request Lookup for customization
* makes parser request creation a bit friendlier
* removes a log of redundancy (same stuff copied over)
* ability to alter rootDirectory detection in parsers
* resident invoker bugfix
* adds UTs for 3 invoker implementations
---
https://issues.apache.org/jira/browse/MNG-8283
New CLI for Maven. Goals are reusability, extensibility and easier embeddability (a la mvnd). If you build this branch, you will end up with Maven distro that uses "new" `maven-cli:org.apache.maven.cling.MavenCling` class as entry point instead of "old" `maven-embedder:org.apache.maven.cli.MavenCli`.
First step is to make "pretty much equivalent" capable CLI as compared to "old", with some exceptions:
* "encryption" ops are gone, those should be in separate tool anyway
* "deprecated and unsupported" CLI options like `-llr` present ONLY to make Maven fail are gone (now Arg parser will fail).
Current state of affairs is messy, MavenCli mixes everything it can, contains interleaved logic for bootstrapping, arg parsing, default logic and executing Maven. First goal is to clean this up.
Commons CLI are also hidden in this PR, so is ClassWorlds. This basically opens up way to have "alternative" CLI arguments parsers as well.
Currently the "local" (CLI) flow is this:
```
arg[] -> localParser -> Request -> localInvoker -> maven runs (in situ)
```
But the point is if you "come up" somehow with a Request instance, one can also do just:
```
Request -> invoker -> maven runs (somewhere)
```
Local parser:
* parses CLI args
* infers the defaults
* creates Request object that contains all information needed to run Maven
* can be reused outside of CLI as well
* does NOT fiddle with Plexus, logging, etc.
Local invoker:
* accepts Request object
* deals with configuring env (logging, etc), creating DI container, and running Maven ONLY
There are some experiments ongoing as well, like `ForkedInvoker` is, but also `MavenTool`.
---
https://issues.apache.org/jira/browse/MNG-8283
