Added 'latest/10k' endpoint for filings

Added ability to retrieve only the latest filing of type 10-K from the /filings/latest/10k endpoint.

Also packaged a Helm chart for easy distribution of the merlin system.

Created sample frontend

Started a sample frontend to showcase the capabilities of the API.

Currently deployed at https://merlin.stevenxie.me.

Initial notes endpoint

Added an initial, rather experimental endpoint for retrieving financial notes for a given CIK and accession number.

Sample request / response:

$ curl https://merlin.stevenxie.me/api/notes/1318605/0001564590-18-002956
[
  {
    "id": 1,
    "title": "Overview",
    "link": "https://www.sec.gov/Archives/edgar/data/1318605/000156459018002956/R9.htm"
  },
  {
    "id": 2,
    "title": "Summary of Significant Accounting Policies",
    "link": "https://www.sec.gov/Archives/edgar/data/1318605/000156459018002956/R10.htm"
  },
// ...

Balance sheets pre-release

This is an API-only pre-release of merlin, featuring the balance sheets endpoint:

Sample request / response:

$ curl https://merlin.stevenxie.me/api/sheets/320193/0000320193-18-000145
[
  {
    "CIK": "320193",
    "accessionNumber": "0000320193-18-000145",
    "date": "Sep. 29, 2018",
    "sections": {
      "currentAssets": [
        {
          "name": "Cash and cash equivalents",
          "value": "$ 25,913"
        },
        {
          "name": "Marketable securities",
          "value": "40,388"
        },
        {
          "name": "Accounts receivable, net",
          "value": "23,186"
        },
# ...