Parseable output in JSON format

[atarantini]

Add new parameter (-o output.json) to store results in a parseable file (json or csv):

$ ./wpbf.com -o output.json http://localhost/wordpress/
2013-03-09 18:03:20,462 - INFO - Target URL: http://vulsai.com/
2013-03-09 18:03:20,475 - INFO - Checking URL & username...
2013-03-09 18:03:20,475 - INFO - Enumerating users...
2013-03-09 18:05:53,331 - INFO - Usernames: admin, andres
2013-03-09 18:05:55,216 - INFO - 89 plugins will be tested
2013-03-09 18:05:55,216 - INFO - Writing results to output.json...

Results may be grouped and look like:

{
    "users": [ "admin", "andres" ],
    "plugins": {
        "contact-form-7": { "version": "1.2.3" },
        "akismet": { "version": "0.1.7" }
    },
    "passwords": {
        "admin": "admin",
        "andres": "1234"
    }
}