Date serialization issue

[cristobalrosa]

Fix date serialization issue.

Since we were not specifying the date serializer the deserialization made by jackson was wrong: Using the java sdk I was retrieving a couple of pulses like this:

Pulse{name='test2', description='aa', tags=[], indicators=[]}
Created Wed Jul 12 16:39:47 CDT 2017
Modified Wed Jul 12 16:39:47 CDT 2017

Pulse{name='test1', description='', tags=[], indicators=[Indicator{indicator='domain.com', type='DOMAIN', description='lll', created=Wed Jul 12 16:08:32 CDT 2017}]}
Created Wed Jul 12 16:21:49 CDT 2017
Modified Wed Jul 12 16:21:20 CDT 2017

And using the python sdk:

 {
    "adversary": "",
    "author_name": "cristobal",
    "created": "2017-07-12T21:08:31.798000",
    "description": "",
    "extract_source": [],
    "id": "xxxx",
    "indicators": [
      {
        "content": "",
        "created": "2017-07-12T21:08:32",
        "description": "lll",
        "id": 27276,
        "indicator": "domain.com",
        "title": "kk",
        "type": "domain"
      }
    ],
    "industries": [],
    "modified": "2017-07-12T21:08:48.752000",
    "name": "test1",
    "public": 0,
    "references": [],
    "revision": 2,
    "tags": [],
    "targeted_countries": [],
    "tlp": "white"
  },
 {
    "adversary": "",
    "author_name": "cristobal",
    "created": "2017-07-12T21:25:07.880000",
    "description": "aa",
    "extract_source": [],
    "id": "yyyy",
    "indicators": [],
    "industries": [],
    "modified": "2017-07-12T21:25:07.880000",
    "name": "test2",
    "public": 0,
    "references": [],
    "revision": 1,
    "tags": [],
    "targeted_countries": [],
    "tlp": "white"
  }

The code I've used to test this is like the following:

package com.alienvault.otx;

import com.alienvault.otx.connect.OTXConnection;
import com.alienvault.otx.model.pulse.Pulse;

import java.net.MalformedURLException;
import java.net.URISyntaxException;
import java.util.List;
public class testOtx {
    public static void main(String[] args) throws MalformedURLException, URISyntaxException {
        OTXConnection connection = new OTXConnection("yourapikeyhere");
        List<Pulse> pulseList = connection.getAllPulses();
        for (Pulse pulse : pulseList) {
            System.out.println(pulse.toString());
            System.out.println("Created " + pulse.getCreated().toString());
            System.out.println("Modified "+ pulse.getModified().toString());
            System.out.println("====================================================");
        }
    }
}