remove `piscine` header and fix typo

subjects/printrange/README.md

@@ -8,7 +8,7 @@ Write a function called `PrintRange` that given a range between two numbers, pri
 - If the number is greater than `9` print only up to `9`
 - If the number is less than '0' print only up to '0'
 - If both numbers are less than `0` print (`'\n'`), the same applies when both numbers are greater than 9.
-- the output must be separated by spaces and (`'\n'`) at the end.
+- The output must be separated by spaces and (`'\n'`) at the end.
 
 ### Expected function
 
@@ -25,16 +25,15 @@ Here is a possible program to test your function:
 ```go
 package main
 
-import "piscine"
 import "fmt"
 
 func main() {
-    piscine.PrintRange(1, 10)
-    piscine.PrintRange(10, 1)
-    piscine.PrintRange(1, 1)
-    piscine.PrintRange(10, 10)
-    piscine.PrintRange(0, 9)
-    piscine.PrintRange(-1, -10)
+    PrintRange(1, 10)
+    PrintRange(10, 1)
+    PrintRange(1, 1)
+    PrintRange(10, 10)
+    PrintRange(0, 9)
+    PrintRange(-1, -10)
 }
 ```