/// <summary>
/// When a letter is clicked, remove it object, pass it value to the game master and increment index
/// </summary>
private void OnMouseDown()
{
index = gM.index;
string currentLetter = letters.transform.GetChild(0).GetComponent<TextMesh>().text;
GameObject.Find(indexEmpty[index].ToString()).transform.GetChild(0).GetComponent<TextMesh>().text = currentLetter;
gM.IncIndex();
gM.AddCharToAnswer(currentLetter);
Destroy(letters);
}