Implement complex file filters

[bgaillard]

It would be very useful to pick files using more complex file filters.

Filters for a set of files :

{
    "id" : "archive",
    "cwd" : "dir",
    "dst" : "archive.zip",
    "src" : {
        "patterns" : ["**/*.png", "**/*.gif"],
        "filters : {
            "creationDate" : {
                "olderThan" : "3D",
                "youngerThan" : "15D" 
            }
            "lastModificationDate" : {
                "olderThan" : "3D",
                "youngerThan" : "15D"
            },
            "mimeTypes" : ["image/gif", "image/png"]
        }
    }
}

Very complex file set, take all PDF file which are not inside the a directory and all the PNG files which have a creation date older than 3 days and all the JPG files which have a creation date younger than 15 days.

{
    "id" : "archive",
    "cwd" : "dir",
    "dst" : "archive.zip",
    "src" : [
        "**/*.pdf",
        "!a/**/.pdf",
        {
            "patterns" : ["**/*.png"],
            "filters : {
                "creationDate" : {
                    "olderThan" : "3D"
                }
            }
        }, 
        {
            "patterns" : ["**/*.jpg"],
            "filters : {
                "creationDate" : {
                    "youngerThan" : "15D"
                }
            }
        }
    ]
}