Fix vevent location backcompat

[gRegorLove]

From https://github.com/microformats/tests/blob/master/tests/microformats-v1/hcalendar/combining.html

<div class="vevent">
  <a class="summary url" href="http://indiewebcamp.com/2012">
    IndieWebCamp 2012
  </a>
  from <time class="dtstart">2012-06-30</time> 
  to <time class="dtend">2012-07-01</time> at 
  <span class="location vcard">
    <a class="fn org url" href="http://geoloqi.com/">Geoloqi</a>, 
    <span class="adr">
        <span class="street-address">920 SW 3rd Ave. Suite 400</span>, 
        <span class="locality">Portland</span>, 
        <abbr class="region" title="Oregon">OR</abbr>
    </span>
  </span>
</div>

Currently parses the vcard as a child instead of location property:

"items": [
    {
        "type": [
            "h-event"
        ],
        "properties": {
            "name": [
                "IndieWebCamp 2012"
            ],
            "url": [
                "http://indiewebcamp.com/2012"
            ],
            "start": [
                "2012-06-30"
            ],
            "end": [
                "2012-07-01"
            ]
        },
        "children": [
            {
                "type": [
                    "h-card"
                ],
                "properties": {
                    "name": [
                        "Geoloqi"
                    ],
                    "org": [
                        "Geoloqi"
                    ],
                    "url": [
                        "http://geoloqi.com/"
                    ],
                    "adr": [
                        {
                            "type": [
                                "h-adr"
                            ],
                            "properties": {
                                "street-address": [
                                    "920 SW 3rd Ave. Suite 400"
                                ],
                                "locality": [
                                    "Portland"
                                ],
                                "region": [
                                    "Oregon"
                                ]
                            },
                            "value": "920 SW 3rd Ave. Suite 400, \n        Portland, \n        Oregon"
                        }
                    ]
                }
            }
        ]
    }
]

I think this line needs to be changed to p-location h-card.

[gRegorLove]

Also affects https://github.com/microformats/tests/blob/master/tests/microformats-v1/hcalendar/attendees.html

[gRegorLove]

Resolved with #234 and #241