Added Remove Tests and Remove Methods

FlexArray/FlexArrayString.cs

@@ -55,6 +55,53 @@ public class FlexArrayString
 
         return false;
     }
+    
+    public bool Remove(string value, bool firstOnly)
+    {
+        var removedAny = false;
+        for (var i = 0; i < Count; i++)
+        {
+            if (value != _data[i])
+            {
+                continue;
+            }
+
+            RemoveAt(i--);
+            removedAny = true;
+            if (firstOnly)
+            {
+                break;
+            }
+        }
+
+        return removedAny;
+    }
+
+    public bool RemoveAt(int index)
+    {
+        if (index < 0 || index >= Count)
+        {
+            return false;
+        }
+
+        if (index != Count - 1)
+        {
+            ShiftLeft(index);
+            
+        }
+
+        Count--;
+
+        return true;
+    }
+
+    private void ShiftLeft(int fromIndex)
+    {
+        for (var i = fromIndex; i < Count; i++)
+        {
+            _data[i] = _data[i + 1];
+        }
+    }
 
     private void Grow()
     {