title: filter jqgrid with multiple "and" and "or" conditions
body: <p>I want to filter jQGrid using below search criteria</p>
  
  <pre><code>Name="Mark" and Age=25 and (city="NY" or city="FL") and (company="xyz" or company="zyx")
  </code></pre>
  
  <p>below is my search string</p>
  
  <pre class="lang-json prettyprint-override"><code>{
      "groupOp": "AND",
      "rules": [{
          "field": "Name",
          "op": "eq",
          "data": "Mark"
      }, {
          "field": "Age",
          "op": "eq",
          "data": "25"
      }],
      "groups": [{
          "groupOp": "OR",
          "rules": [{
                  "field": "city",
                  "op": "eq",
                  "data": "NY"
              },
              {
                  "field": "city",
                  "op": "eq",
                  "data": "FL"
              }
          ],
          "groups": [{
              "groupOp": "OR",
              "rules": [{
                      "field": "company",
                      "op": "eq",
                      "data": "xyz"
                  },
                  {
                      "field": "company",
                      "op": "eq",
                      "data": "zyx"
                  }
              ]
          }]
      }]
  }
  </code></pre>
  
  <p>and </p>
  
  <pre class="lang-js prettyprint-override"><code>postData: {
      filters: above string
  },
  </code></pre>
  
  <p>but this search is not working. please help</p>