feat(challenges): add print-pyramid

challenges/print-pyramid/README.md

@@ -0,0 +1,50 @@
+# print-pyramid
+
+Created by [@Divlo](https://github.com/Divlo) on 21 September 2021.
+
+## Instructions
+
+Display a pyramid of stars (`*`) whose height is given and in the right order (`normal` or `reverse`).
+
+### Input
+
+- **Line 1:** The string : `normal` or `reverse` to determine how to show the pyramid.
+- **Line 2:** The integer : height of the pyramid.
+
+## Examples
+
+See the `test` folder for examples of input/output.
+
+### Example 1
+
+#### Input
+
+```txt
+normal
+3
+```
+
+#### Output
+
+```txt
+  *
+ ***
+*****
+```
+
+### Example 2
+
+#### Input
+
+```txt
+reverse
+3
+```
+
+#### Output
+
+```txt
+*****
+ ***
+  *
+```