doc: use markdown for english requirements

GildedRoseRequirements.md

@@ -0,0 +1,37 @@
+# Gilded Rose Requirements Specification
+
+Hi and welcome to team Gilded Rose. As you know, we are a small inn with a prime location in a
+prominent city ran by a friendly innkeeper named Allison. We also buy and sell only the finest goods.
+Unfortunately, our goods are constantly degrading in `Quality` as they approach their sell by date.
+
+We have a system in place that updates our inventory for us. It was developed by a no-nonsense type named
+Leeroy, who has moved on to new adventures. Your task is to add the new feature to our system so that
+we can begin selling a new category of items. First an introduction to our system:
+
+- All `items` have a `SellIn` value which denotes the number of days we have to sell the `items`
+- All `items` have a `Quality` value which denotes how valuable the item is
+- At the end of each day our system lowers both values for every item
+
+Pretty simple, right? Well this is where it gets interesting:
+
+- Once the sell by date has passed, `Quality` degrades twice as fast
+- The `Quality` of an item is never negative
+- __"Aged Brie"__ actually increases in `Quality` the older it gets
+- The `Quality` of an item is never more than `50`
+- __"Sulfuras"__, being a legendary item, never has to be sold or decreases in `Quality`
+- __"Backstage passes"__, like aged brie, increases in `Quality` as its `SellIn` value approaches;
+	- `Quality` increases by `2` when there are `10` days or less and by `3` when there are `5` days or less but
+	- `Quality` drops to `0` after the concert
+
+We have recently signed a supplier of conjured items. This requires an update to our system:
+
+- __"Conjured"__ items degrade in `Quality` twice as fast as normal items
+
+Feel free to make any changes to the `UpdateQuality` method and add any new code as long as everything
+still works correctly. However, do not alter the `Item` class or `Items` property as those belong to the
+goblin in the corner who will insta-rage and one-shot you as he doesn't believe in shared code
+ownership (you can make the `UpdateQuality` method and `Items` property static if you like, we'll cover
+for you).
+
+Just for clarification, an item can never have its `Quality` increase above `50`, however __"Sulfuras"__ is a
+legendary item and as such its `Quality` is `80` and it never alters.

GildedRoseRequirements.txt

@@ -1,38 +0,0 @@
-======================================
-Gilded Rose Requirements Specification
-======================================
-
-Hi and welcome to team Gilded Rose. As you know, we are a small inn with a prime location in a
-prominent city ran by a friendly innkeeper named Allison. We also buy and sell only the finest goods.
-Unfortunately, our goods are constantly degrading in quality as they approach their sell by date. We
-have a system in place that updates our inventory for us. It was developed by a no-nonsense type named
-Leeroy, who has moved on to new adventures. Your task is to add the new feature to our system so that
-we can begin selling a new category of items. First an introduction to our system:
-
-	- All items have a SellIn value which denotes the number of days we have to sell the item
-	- All items have a Quality value which denotes how valuable the item is
-	- At the end of each day our system lowers both values for every item
-
-Pretty simple, right? Well this is where it gets interesting:
-
-	- Once the sell by date has passed, Quality degrades twice as fast
-	- The Quality of an item is never negative
-	- "Aged Brie" actually increases in Quality the older it gets
-	- The Quality of an item is never more than 50
-	- "Sulfuras", being a legendary item, never has to be sold or decreases in Quality
-	- "Backstage passes", like aged brie, increases in Quality as its SellIn value approaches;
-	Quality increases by 2 when there are 10 days or less and by 3 when there are 5 days or less but
-	Quality drops to 0 after the concert
-
-We have recently signed a supplier of conjured items. This requires an update to our system:
-
-	- "Conjured" items degrade in Quality twice as fast as normal items
-
-Feel free to make any changes to the UpdateQuality method and add any new code as long as everything
-still works correctly. However, do not alter the Item class or Items property as those belong to the
-goblin in the corner who will insta-rage and one-shot you as he doesn't believe in shared code
-ownership (you can make the UpdateQuality method and Items property static if you like, we'll cover
-for you).
-
-Just for clarification, an item can never have its Quality increase above 50, however "Sulfuras" is a
-legendary item and as such its Quality is 80 and it never alters.

README.md

@@ -20,7 +20,7 @@ Please don't send me a pull request with your solution. It can be a bit confusin
 
 ### Gilded Rose Requirements in other languages 
 
-- [English](GildedRoseRequirements.txt)
+- [English](GildedRoseRequirements.md)
 - [Español](GildedRoseRequirements_es.md)
 - [Français](GildedRoseRequirements_fr.md)
 - [Italiano](GildedRoseRequirements_it.md)