Couple of field name typos

[konklone]

At https://www.govinfo.gov/bulkdata/json/BILLSTATUS/115/s I saw a couple of typos in field names, displayLable and fileExtention:

{
"mimeType": "application/xml",
"size": "17.4 kB",
"lastModifiedTime": 1491269941000,
"fullFileName": "BILLSTATUS-115s17.xml",
"name": "BILLSTATUS-115s17.xml",
"fmtLastModified": "04-Apr-2017 01:39",
"folder": false,
"displayLable": "BILLSTATUS-115s17.xml",
"cfrTitle": 0,
"justFileName": "BILLSTATUS-115s17.xml",
"fileExtention": "xml"
}

[jonquandt]

partially fixed -- looks like the fileExtention -> fileExtention fix didn't make it in this release. I'm going to create that as a separate issue and close this one for easier tracking, @konklone

[jonquandt]

Closing #55