docs(notdecimal): fix subject

- fix folder name
- fix exercise name
- upgrade instructions
- add missing import piscine
- fix white-spaces and indentation

subjects/not_decimal/README.md

@@ -1,49 +0,0 @@
-## not_decimal
-
-### Instructions
-
-Write a function called `Not_decimal` that takes a string in forme of a float number with the decimal point and returns an integer without the decimal point (you muliply by 10^n to remove `.`).
-
-- If the number is doesn'the have a decimal point or  there is only zero after `.` return the number followed by a newline `\n`.
-- If the argument is empty return newline `\n`.
-- If The argument is not a number return it followed by newline `\n`.
-
-### Expected function
-
-```go
-func Not_decimal(dec string) string {
-}
-```
-### Usage
-
-Here is a possible program to test your function :
-
-```go
-package main
-
-import "fmt"
-
-func main() {
-	fmt.Print(Not_decimal("0.1"))
-	fmt.Print(Not_decimal("174.2"))
-	fmt.Print(Not_decimal("0.1255"))
-	fmt.Print(Not_decimal("1.20525856"))
-	fmt.Print(Not_decimal("-0.0f00d00"))
-	fmt.Print(Not_decimal(""))
-	fmt.Print(Not_decimal("-19.525856"))
-	fmt.Print(Not_decimal("1952"))
-}
-```
-And its output :
-
-```go
-$ go run .  | cat -e
-1$
-1742$
-1255$
-120525856$
--0.0f00d00$
-$
--19525856$
-1952$
-```

subjects/notdecimal/README.md

@@ -0,0 +1,53 @@
+## notdecimal
+
+### Instructions
+
+Write a function called `NotDecimal()` that takes as an argument a `string` in forme of a float number with the decimal point and returns a string converted to an `int` without the decimal point (you will have to multiply it by 10^n to remove the `.`).
+
+- If the number doesn't have a decimal point or there is only a zero after the `.` return the number followed by a newline `\n`.
+- If the argument is empty return newline `\n`.
+- If the argument is not a number return it followed by newline `\n`.
+
+### Expected function
+
+```go
+func NotDecimal(dec string) string {
+
+}
+```
+### Usage
+
+Here is a possible program to test your function:
+
+```go
+package main
+
+import (
+	"fmt"
+	"piscine"
+)
+
+func main() {
+	fmt.Print(piscine.NotDecimal("0.1"))
+	fmt.Print(piscine.NotDecimal("174.2"))
+	fmt.Print(piscine.NotDecimal("0.1255"))
+	fmt.Print(piscine.NotDecimal("1.20525856"))
+	fmt.Print(piscine.NotDecimal("-0.0f00d00"))
+	fmt.Print(piscine.NotDecimal(""))
+	fmt.Print(piscine.NotDecimal("-19.525856"))
+	fmt.Print(piscine.NotDecimal("1952"))
+}
+```
+And its output:
+
+```console
+$ go run .  | cat -e
+1$
+1742$
+1255$
+120525856$
+-0.0f00d00$
+$
+-19525856$
+1952$
+```