Added articles in markdown

Added all (missing) current articles of each quadrant.

radar/2017-03-01/hal-hateoas.md

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+---
+title:      "HAL / HATEOAS"
+ring:       assess
+quadrant:   methods-and-patterns
+
+---
+Hypermedia As The Engine Of Application State or in short HATEOAS is a pattern that helps to organize dependencies and resources in a RESTful API. The basic idea of HATEOAS is that an API consumer do not have to know how dependencies of resources are connected and how to get them. A consumer must only be familiar with the basics of hypermedia.
+
+Let's assume we have a bank account and an action to deposit money on that account. Everything you need to know is that the account resource has an action for a deposit. The URL of that action can then fetched from the link attribute with the corresponding relation.
+
+`<account>`
+
+`    <account_number>12345</account_number>`
+
+`    <balance currency="usd">-25.00</balance>`
+
+`    <link rel="deposit" href="https://bank.example.com/account/12345/deposit" />`
+
+`</account>`
+
+
+Besides from HATEOAS there is an alternative implementation called Hypertext Application Language, in short HAL, which has much more features than the basic HATEOAS.
+
+With HAL you are allowed to also define parametrized links, embedded resources and a documentation relation between resources which are called curies. You can find the specification [here](http://stateless.co/hal_specification.html).