New feature `sanitizeOutput(recursiveKeys: [], pattern_ignore: [])`

[LouisLeNezet]

I'm looking for a nice way to snapshot the output of a directory from a process output.
The aim would be to recursively output the files in a directory and put either the name or the md5 depending on patterns.

For the moment I'm doing:

{
    def stable_name = getAllFilesFromDir(process.out.db[0][1].toString(), include:['*', '**/*'])
    def stable_content = getAllFilesFromDir(process.out.db[0][1].toString(), include:["**/VERSION", "**/animal_mt.fasta"])

    assert snapshot(
        stable_name*.name.sort(),
        stable_content,
        process.out.findAll { key, val -> key.startsWith('versions') }
    ).match()
}

My aim would be to have something like:

{ assert snapshot(sanitizeOutput(
    process.out,
    recursiveKeys: ["db"],
    stableFiles: ["**/VERSION", "**/animal_mt.fasta"]
).match() }