feat: Turtle.VerticalLine becomes v ( Fixes PoshWeb#281 )

Author: StartAutomating

Types/Turtle/Alias.psd1

@@ -5,8 +5,9 @@
     c = 'CubicBezierCurve'
     l = 'Step'
     h = 'HorizontalLine'
-    s = 'BezierCurve'
     q = 'QuadraticBezierCurve'
+    s = 'BezierCurve'
+    v = 'VerticalLine'
 
     # Shorter forms:
     Pie = 'PieGraph'

Types/Turtle/VerticalLine.ps1

@@ -5,10 +5,22 @@
     Draws a vertical line.  
     
     The heading will not be changed.
+.EXAMPLE
+    turtle VerticalLine 42
+.EXAMPLE
+    turtle VerticalLine 42 pathdata
 #>
 param(
+# The length of the line.
 [double]
 $Distance
 )
 
-$this.GoTo($this.Position.X, $this.Position.Y + $Distance)
+$instruction = 
+    if ($this.IsPenDown) {
+        "v $Distance"
+    } else {
+        "m 0 $($this.Position.Y + $Distance)"
+    }
+$this.Position = 0, $Distance
+$this.Steps.Add($instruction)