private void ShowEntireFileToolStripMenuItemClick(object sender, EventArgs e)
{
showEntireFileToolStripMenuItem.Checked = !showEntireFileToolStripMenuItem.Checked;
showEntireFileButton.Checked = showEntireFileToolStripMenuItem.Checked;
ShowEntireFile = showEntireFileToolStripMenuItem.Checked;
OnExtraDiffArgumentsChanged();
}